Most of the gay host bars in Pattaya are located in Jomtien Complex, aka Supertown,with a few in Boyztown and 2 or 3 in Sunee Plaza. Basically you look around and find one which looks interesting, sit down and order a drink of choice. There should be many boys in attendance and just ask one who attracts you if he would like a drink. Sunee Bar is popular as is ? Bar and Jewel Bar and M Bar, with many lads anxious to help you. But all the bars have lads to meet your tastes. If you meet someone who interests you, then off them and go to your room or rent a short time room. M Bar conveniently has a short time room available at a reasonable cost. If a boy does sit with you, pay for his drink and give him a tip of 100 Baht at least. If you off him there will be a fee of about 400 Baht plus a tip of 1000 B or more depending on your experience.
I recall an experience at Jewel Bar where a nice young man always stopped me and we had a chat and exchanged names but nothing further. Then I had a revelation and offered him a drink and ever since had a great time with him.