Need Help With Picking!

I created an opengl program where you use can create move and delete polygons… I am currently using a bounding box to pick a polygon that i created. i know that opengl offers picking. can anyone please lead me towards the right direction so that i can convert my program to use picking instead of a bounding box to select a polygon that i created?

thank you…

Please let me know if you need more information!

oh yea i wrote it in C…