Here's what I do using FL Studio 9 producer's edition:
1.) Brainstorm and choose a song from my music collection
2.) Load the song into Edison and highlight the piece of the song I want to use
3.) Drag the sample onto the step sequencer, select the new channel it's in
4.) Then I just fux wit it. Reverse it, speed it up, slow it down, change the pitch, put it on the mixer and add effects or EQ out any unwanted parts to the best of my ability, etc. This is the step that takes the longest and requires the most creativity and the "producer's ear" that I haven't quite developed yet.
It really depends on the style you're going for and you're only limited by your skill level. Watch tutorials, read interviews, articles, whatever you can find on the subject.
I like that "LifeTime" beat you put together, that was nice