Depends on the age of the child. To be honest , if they are ready , they will find it no bother, just the usual running along with them, shouting encouragement. If they are not ready and are afraid, forget it. Eventually , they'll do it themselves when they see their pals doing it and it's not worth making a big deal out of it.
We started in a local park that has some gentle grassy slopes. We started off letting them down the slope on the bike with stabilisers, then took off the stabilisers and let momentum and gravity move them down the slope, with me running alongside to make sure there were no accidents.
My daughter's best friend has being cycling since she was 3 - she started off on one of those German bikes with no pedals.
.