There's no time frame or post count for becoming a guide. Guides are users of the site who are recognized for their helpfulness. Some have called Guides "junior moderators", but their responsibilities are much greater than that. It is true that most if not all the moderators here were guides at one time. There's no formula for becoming a guide, but I can tell you that being considerate and helpful are great starts. Not sticking to one small part off the site is another step in the right direction.
, follow them and prosper!
Did you forget to kiss a Mod today?