@Stephen ********
okay. So you are currently stamped in for 60 days which you can extend for another 30 days at your local immigration office then you have a couple of choices depending on what you want to achieve and how long you want to stay. At the end of the 90 days you will need to leave Thailand to a nearby country and then you can return...
1. If all you want is another 60 days and have no prior history in Thailand you can just cross a border and return for that although normally best to spend a night or 2 outside Thailand but you can potentially only do this once
2. If you want to spend much longer in Thailand, and you are over 50, you could apply for a 90 day Non-O visa at the Thai consulate of country you travel to before returning. Then you can open a Thai bank account, place 800k baht in it and apply for a 12 month extension of stay