With that in mind, the first suggestion is that as a Farang, you don't need a Thai driving license. Assuming you don't break any major rules, the most important being that you're wearing a helmet while on a bike, you should be fine. Don't drive like an idiot and you won't stick out in the crowds (which seems to have worked fine for fish over the millennia, and who am I to second guess millions of years of evolution?). From what I can gather from my six months of socializing with various members of community police officers, it would be extraordinarily embarrassing for a policeman (sorry, I usually strive for gender-neutrality, but here it's just not appropriate. In my [admitedly limited] experience, the Thai Police force is limited to men only.) to pull over a farang. It has to do with the complicated cultural-socio etiquette that revolves around losing face: to be involved in a public disturbance, such as would occur by pulling a farang over, the police officer would be shamed as much as the farang. Note: This isn't a license to speed, act improper, or abuse the system. It's more of a way of allowing the local police to avoid the unpleasantness that would occur after an arrest. Further, this applies strongly when the farang in question is an ajarn (teacher) because they are well respected within the community. The disinclination to pull a farang over erodes quickly in larger cities and in cases where the individual isn't known or respected in the community. I would recommend treading very lightly at first, or avoiding driving without a license altogether in larger cities such as Bangkok. Finally, if you tend to break or stretch cultural norms, for example as a female being seen drinking or smoking in public, you might not apply to this exemption. One unpleasant fact of life in Thailand (at least for Westerners used to a generally equal treatment [while acknowledging that there is still work to be done, especially in regards to equal pay for equal work]) is that there is a double standard for gender here, which is particularly strong in regards to etiquette. Breach those standards and you may find yourself in unpleasant circumstances. This isn't a value judgement, just a statement of the facts as I see them as they relate to this issue. 

That said, it's been intimated to me by multiple sources that the best solution other than actually getting an international driver's license if you're going to be here for an extended stay is to get a letter, on letterhead, from the school or business you're working with, in Thai, stating your name, address, and the conditions of your employment, including the length of your stay. If you were pulled over, you would be able to at least show the arresting officer that you are here, working in some capacity, and that there are Thai citizens benefiting from your stay. This, according to the individuals I've spoken to, would be more than enough to assuage any concerns the arresting officer had in any but the most extreme situations. End result? Don't drive like an ass, and don't put others or yourself at risk, and Thailand will welcome you with open arms, glad that you're sharing in their wonderful culture and hopefully sharing a bit of yours at the same time.

Second: Don't assume that because a gigantic truck with blue and red lights flashing comes bearing down on you that you're in for an stop. The blue and reds that I associate with police actions in the States are available at most larger markets out here, and as Thais love to add lights, paintings, and anything else that's colorful to their vehicles, don't think that the blue and red is unique to the police. Every traffic stop I've seen has involved a lone policeman or two standing next to their bikes, politely waving with a down-turned hand in the Thai way, to the occasional biker driving without a helmet, who invariably pull to the side of the road, take their ticket, then put the helmet that is sitting in the basket of their bike on, and drive away. That said, of course, always yield to emergency vehicles, or really any vehicle bigger than you. Streets can be chaotic here! See point number three!

Third: Don't expect that a one way street will remain that way. While bike are notorious for driving the wrong way on what is ostensibly a one-way street, I've seen everything do it from motorcycles with dining carts attached to large semis out here. Just make sure you look both ways, usually twice, before committing to any move in serious traffic. 

Fourth: expect feral dogs, especially in the more rural areas. There's one dog who lives at the end of my street, the tiniest little mangy thing, that's the bane of my morning commute. The second I pass him on my bike, he's off and running as fast as his little legs can carry him, jumping and nipping at my heels. Sometimes he even fakes being asleep to give me a false sense of security. I'd imagine he's mostly harmless, but you've also got to avoid the larger dogs, who tend to sit in the street warming themselves, who are little motivated to move for anything smaller than a car. Be ready to swerve in your best imitation of the old coin op video game Paperboy. Just be thankful there are no killer bees or whatever else that game threw at you while trying your best to make an honest buck delivering newspapers in suburbia. 

Fifth: This one really only applies to scooters. If you're in short sleeves, (which you shouldn't be. As an avid, if lapsed, motorcyclist, I recommend always wearing appropriate gear that might save you from a skin graft or two in the result of a fall. I've got enough of my ass permanently stapled to my arm for one lifetime, and really, any is too much. Keep your ass where it belongs, and wear the right gear.) wear sunscreen. Rule number 5 was discovered to the detriment by an old roommate of mine, who toured rural Thailand for a day with a rented bike, and ended up with second degree (that's really bad) burns over most of his forearms from the sun. You don't realize it when you're dodging dogs, other bikes, Pad Thai carts, and herds of cattle, but the tropical sun will pwn your exposed arms out here given the chance. 

Sixth: Don't expect turning traffic to yield to you. Thai drivers seem to think that bikes are so maneuverable that you can avoid them when they pull out without looking at an intersection. Mostly they're right- a bike when ridden well can do almost anything. That applies doubly to a scooter, which is very stable, but still, ride cautiously, especially at intersections. The natural tendency for drivers here seems to be accelerate first, and then check and make sure that no one's coming in the opposite direction.

That about sums it it for now. I suppose I should add a corny rule like seven: have fun and appreciate all the new things you'll see on your adventure, but in tribute to the creator of Holden Caulfield, who passed away recently, I'll leave the phony stuff out and just say facing (admittedly minor) challenges such as this have made me more happy than not in my time out here. Stay safe and wear a helmet!