How and when do you ask for referrals?

i read the thread on compensating for referrals but lets start at the bottom… how and when do you ask for referrals? i get my fair share but always feel like i could increase my business by 30-40% if i really pushed for them.
care to share some ideas?

I try to take any positive comment they make at the end of (or during) the job as an opportunity to mention more frequent cleanings (monthly outs if possible) and give them a few business cards to pass out to their friends and family. In fact I’m doing a job tomorrow that is the son of a recent first time client. We came highly recommended by his mother and that was the biggest reason we got the job.

I work almost exclusively off of referals because I like the pricing edge it gives me. At billing I always leave 3 to 6 cards and ask if they know of anyone else that may be interested in having their windows cleaned.

[B]THEGLASSMACHINE[/B]
[I]“because glass looks it’s best when you can’t see it”[/I]