Take it first thing in the morning on an empty stomach (usually no more than 2mg). I then wait at least an hour before eating. It then usually starts being effective about 3 hours after I've initially taken it.
I find the effects of Robinul tends to wear off a bit by about 4pm-5pm if I take it at 7am. If I'm outside and it's boiling hot it has only a minimal effect. This happened to me recently at a wedding...very very uncomfortable.
Side Effects for me are - dry mouth and eyes, sometimes a light headache and facial blushing.