no problem. and welcome to the board.
theres 2 ways. go to the bar and sit down and spot a girl you like. show some interest and she will come over to you. you can buy her a lady drink(usually 120baht,3usd). if you are getting along chances are she will ask you if she can come with you. i dont really like getting involved with girls that talk money, and if they dont, it usually means they are happy to go with you and get what you give them in the money(which unwritten rule is lowest 1000baht). but if you feel more comfortable, you can ask her that much. if agreed, you can choose to stay in the bar, or you can ask for your bill, wghere her bar fine, 200-300baht,500 in go-go, will be added