Wrist Curls?

I am a newbie and have just discoverd the beauty of wrist curls. Only I don't know how many reps, sets, and days a week I should be doing them. Should I do these on the days I do my bis?

Any help would be great.
Thanks

I wouldnt do them within 2-3 days of training back as you will have trouble gripping the bar.
Wrist curls are ok but try doing them behind the back, static holds are also a good forarm exercise, as are hammer curls and reverse grip barbell curls.