How to improve social skills?

Hey im 17 and kinda lack social skills, ive always lacked them to be honest, even since i was 4 i used to play with leaves rather than talking to ppl lol. I had dispraxia (nothing big, just means it was harder for me to talk when i was young,) but that was all fixed up through therapy, although i am really bad at comprehension which is one of the later affects of dispraxia apparently. Anyway, im kinda awkward in social situations cos i dont really know what exactly to say, and im especially pathetic on the phone. Does any1 know how to improve skills in these areas? i know practice makes perfect, but it can b hard to come by especially when u dont want to screw up opportunities, thanks the the help :-)