In Australia, the community is safe enough. I never witnessed any particular fight, and I heard a police car around just once or twice a week.
Many of the students were interested in Japanese culture. As the crucible has various races and cultures, Residents/people tend to respect each other. (In particular, I felt that it was uncivilized to complain about a person's appearance.)

As soon as I arrived at Brisbane airport, I bought a Vodafone pocket Wi-Fi.  It was convenient to use, as it is prepaid and you can replenish your available bandwidth through the app at any time. During my stay, I used the pocket Wi-Fi for sightseeing and shopping. 

White taxis that are not legally available in Japan, are available in Australia in the form of Uber cabs. And I used Uber to commute to and from Brisbane Airport and Griffith University.
Before I actually used it, I was worried what if I encounter a bad driver who would snatch my belonging or something.  However, Uber cabs have an ID for each driver, and you can browse through the ratings of previous customers (like reviews on a mail order service), so in a way it is safer and more convenient for us than public taxis.  The drivers are friendly and helpful so I didn't have to worry about the awkwardness of the whole trip.
The driver said, "There is a very dangerous spider in Brisbane that is poisonous, so be careful" (I don't know if this is true or not), to which I replied, "Well, if it bites me, I might become Spiderman.”　And they replied: "Hahaha!　You have said such an interesting thing!” (I never encountered such a spider during my stay).　

The first thing I was told by my supervisor there was that since Australia is a very informal country, I should call them by their first names even if it was my supervisor.  In fact, when I accidentally call my colleagues in the laboratory with Ms. or Mr., I was frowned upon.  It's a good idea to call each other by a first name or a nickname in the spirit of "when in Rome, do as the Romans do.

Wi-Fi was available in the shared dormitory.Since it was open, it would be better not to enter any important personal information through the Wi-Fi.It was sometimes difficult to get a connection, but it was not usually a problem, as I could make Skype calls without any problems. The Wi-Fi in the research facilities is only available to members of the university, and it was fast and comfortable to use.

For the purpose of applying for the dormitory, I informed my supervisor in advance that I would like to stay the dormitory, and someone from the student support office there help me with that matter. There were two options: a room with private bathroom and kitchen or just bedroom only with common bathroom and kitchen.  I would recommend the latter option because we can have more opportunities to communicate with students from other countries.

When I went to the nearby shopping mall for grocery shopping, I used the public bus.  In Australia, there is a card called "Go Card" to facilitate the payment process (just like PASPY in Japan), and the card itself and the fee can be bought and charged at the university store (just like Co-op in Hiroshima University).

On holidays, it would be better to do something, which are specifically unique to the area if possible (sightseeing, communicating with the locals, etc.).　Let me suggest to eat nutritious food because if you are hesitant to spend, you cannot have enough energy.  I didn't have a chance to speak long sentences in English, nor did I have a chance to give tips. 
When you are not using your wallet, it is better to hide it in a place where people will not see it. I didn't have any trouble during this strip, but it might be a good idea to refrain from saying or doing things which may imply as if you have a lot of money.　

＊I saw a bird and a lizard on the Nathan campus. Both of them are about 1 meter long and very big.  When I arrived at Griffith University, I asked the man who took me to the research facility, "Is it okay to catch those birds and lizards?”  He said, "If you catch them, the police will also catch you. Is it okay?” (not sure if it is true).  So, I was careful not to lay even a finger on them. 
 

At the Quantum Dynamics Research Center, where I was dispatched for this internship, basic research on quantum mechanics and applied research in interdisciplinary fields incorporating various quantum technologies are being conducted theoretically and experimentally.  The research group I joined during the visit is conducting a basic research on quantum mechanics using light, which is almost the same as my own research theme. 
It seemed like there was at least one Japanese in the same research center, but I did not have a chance to talk to him.  I went to Australia from March to May, which is autumn in Australia, and the temperature was around 30 degrees Celsius at the hottest and 20 degrees Celsius at the coldest. The air condition in the lab and on the bus was very strong, so if you are sensitive to the cold, it might be better to prepare something light to wear.  The research institute was about five-minute walk from the dormitory, so I had no problem wearing sandals except when doing experiments.

As a member of the above-mentioned research institute, I learned knowledge and techniques related to applied research on optics while carrying out my research plan, and also expanded my own knowledge through discussions in English with students from overseas.
In the shared student dormitory for this program, I got the chance to learn the position of Japan from the eyes of the world and the differences in the common sense of each country by interacting with students from various countries, specifically, we prepared the optics and electronics for fast switching of optical pulses, and conducted test experiments using CW lasers to check the response of Pockels cell drivers and photodiode detectors. 

Since I already had some experience in handling optical elements, the transition to the experiments was smooth after I learned about the purpose and content of the research from my supervisor and colleagues.
After confirming the basic rules in the lab, I spent most of my time solving problems by myself.  Of course, I had discussed the problems and report the progress with my colleagues and supervisor, and they had listened to me sincerely even though I communicated with my broken English. 

About a week before my return to Japan, I got a chance to give a presentation on what I had done so far in front of my lab mates and supervisor.  I was glad that I was able to convey what I had been thinking and how I had proceeded with my experiments without any problems such as hyperventilating due to nervousness.

I think the most important thing for me was the experience of cross-cultural exchange.
t was not just a matter of communicating with people from other countries (although it can be done in Japan if you just want to talk with them).  Of course, each country has its own culture, common sense, and atmosphere. It is a privilege for those who have been to a country to be able to experience this firsthand.
For example, even though we can't speak a foreign language fluently, the experience of being able to understand each other if we want to know each other is as different as if we didn’t actually do it.  That experience was the biggest change for me before and after the internship.  By gaining various ways of thinking and perspectives through the exchange, I think I am now able to think about things from a broader perspective.

What I gained by trying something new this time was beyond my imagination.  There will be much more chances in the future when such an opportunity comes (or I will be engaged in such opportunities).  Even if I can't completely get rid of my anxiety, I am confident that this internship experience will push me forward.
I believe that it is not something that you intentionally make use of, but something that you unconsciously make use of.

As for the visa, I was instructed by the Immigration & Relocation Adviser at Griffith University to get an "ETA subclass 601" since my stay is less than three months.  As for preparations regarding what to bring from Japan, it is a good idea to do some research on various internet sites beforehand and bring only what everyone says is necessary.   Making a list will help you prepare more efficiently. 
Although there is no specific time for doing research, it would be better to come to work and go home at roughly the same time to avoid making your colleagues worried for you in the same lab.  It is better to communicate important matters clearly, even if you have to use gestures or pictures.  If you are going to be away for a long time or need to take a day off, be sure to let people know. When it comes to research, it is important to have you own clear opinion. 
Although you may have to rely heavily on the people around you who support you in various ways, in the end you should think carefully and make your own decisions.  A passive attitude of "I did it because the people around me told me to" will diminish the precious experience you have gained. Instead of thinking that you will regret it if it doesn't go as expected, you can be positive if you think that it's a good experience to not go as expected.

Everything will be fine, if we can devise a way to enjoy.