Yes, have them lie down. Have them close their eye (leave it open if they will) put the drop in the corner of the eye by the bridge of the nose. Keep them lying down for a few minutes (after they first open the eyes). The drops will go in and spread. try not to let them sit up or rub for a few minutes.
This what what the doctor I used to work for suggested. It does work great. Works for adults too :-)