Could you . . . . (for me) ?
Would you please . . . ?
Would you mind V+ing . . . .?
Could you possibly . . . ?
Okay, no problem.
Sure, I'd be glad to.
Sorry, I'm (kind of) busy now.
I'm sorry. I don't have time right now.
Do you have a minute?
Can you spare a few minutes?
Could you do me a favor?
Could I ask you a favor?
Can I ask you to . . . ?
I need some help (if you have time).
(If you're not busy) I could use your help.