Bike commuting has done my body and soul a lot of good. Some tips
1) Eye contact is key. I've ridden in Yangon before with good results but you really want to see the eyes of drivers to get a sense of how observant they are and make sure they see you before you cross their path.
2) Fenders are very helpful on a commuter bike.
3) If you can put your bike indoors at your workplace that is best. Locking outside can work if the security of the environment is good.
4) Agreement with others - 12km is a great distance; good routing is so vital to safety and enjoyment.
5) It's worth having tires that are puncture resistant to avoid having to change a flat on the way in. Continental and Schwalbe have some that have layers built into the tread that fight cuts.
6) If you get off the side of the road to a parallel sidewalk or other alternate side-of-the-road path, know that you have left the radar of cars and you need to be extra cautious at any driveway or intersection
7) I use a "take-a-look" brand mirror on my glasses to see behind me continuously
8) Having spare pants and socks at work is good. In tropical rain probably having a complete spare change and access to a dryer is good. )