First go as a tourist and you will see on the spot, some troubles at the beginning is part of the process of natural selection between the motivated people and the simple dreamers who hope that they will be taken care of in Thailand like in UK. It is your own skills that will determine if you can find a job, for example a web designer will always find a website to do here or there, in very touristic areas. A chef or baker will have a good chance of finding a job. A TEFL graduate will be able to teach English everywhere. What you will not find are the server jobs or other unskilled jobs.
Be careful the young penniless job seekers can fall into the drug business which is an easy way to stay in the country, or even stay there for a long time between 4 walls, when it is not between bed sheets. The most important thing is to always stay up to date the visa, no overtaking. There are some who let themselves be overwhelmed, who let their visa expire and find themselves trapped. Do not be a phantom student! Thai immigration to which you have to present yourself every three months may speak to you in Thai to see if you studied Thai well and speak Thai is not a piece of cake. On the spot job are very rare except as dive instructor, English teacher or computer related jobs. There is much demand though for teaching jobs in Thailand for foreigners and you can easily check them out at the job portals online. The best remains to be dedicated and not treat working in Thailand as a vacation!