As your new Thai SIM, we checked with AIS 3G for monthly fee in this case you should be contact by yourself. Can’t provide power attorney to someone to do.
Because their require your copied passport ,work permit and credit card.
The process very easy doesn’t take so much time .You just work in to AIS shop inform them what do you what ka ? Please see my links AIS Shop.
http://www.ais.co.th/Default.aspx