As I’ve already talked about earlier in this book. I always bring as little as possible. It’s just a pain in the ass dragging around a ton of stuff that you don’t really need. I don’t even bring toiletries. You can buy small handy deodorants, toothbrushes etc on every 7/11 in Thailand for a fraction of the price back home. I use them for a week, then I buy new.
Here’s a few things however that you should bring from home:
Bring your favorite condoms. Bring a lot of them. You will need them. The condoms in Thailand is not always of good quality. If you are outside the biggest tourist areas they might be expired too (Thai men rarely buy condoms) or you might not find a condom that fit.
Stuff like Imodium, painkillers and stomach regulating herbs/medicine that you know work for you. You can of course get all this in Thailand too, it’s just that illness usually happens when you least expect it. It’s nice to have some basics with you at all times.