use google there are many guides.... my guide to you is this:
step 1) dont do it
step 2) get to a counselor and work out what drove you to use dope. your obviously in a rush and thats never good..
All 3 of those links can be found in the OD Directory at the top of the forum or linked in my signature. If you search around OD and further probe the directory, you'll find even more.
PM me if you have any questions but please, really consider not doing this. The jump to needle for a lot of people is the point of no return.