Reflective ankle bands, or reflectors on your pedals work very well. They will pick up the lights of the traffic around you and the movement is easy to spot and suggests to people it is a bicycle (nothing else moves like that).
Again something nice and reflective on your body is good, it's a big area to be seen and their lights will make it visible.
Two rear lights, one flashing, one solid and fairly bright. This is your protection against people with poor lights. Two because one might fail. Flashing for the movement, solid so you are always lit.
I use two lights on the front, one flashing to be seen and one a beam to see by. Again part of that is if one fails you have another one to hand although at least with the front you can tell.
Some lights are rechargeable with a USB socket, personally I don't like them as I prefer to be able to put new batteries in if the lights go low. This is because I'm likely to forget to charge them at some point. Lights with a warning indicator when the charge is low help get round this.
Finally, as mentioned, ride defensively, give yourself room to move out of the way if someone is bearing down on you. I don't know what the road traffic laws/expectations are in Thailand, but it is worth knowing what you are allowed to do, and taking in to account what other road users are likely to expect.