We are very vigilant about checking the backs [and sometimes tops....and on occasion stems] of each squash leaf for these eggs. When we find them, we pinch them off and squash them, put them in water and feed them to the chickens.
The lighter golden they are, the fresher they are. The darker they are, the closer to hatching they are.
Check your plants every few [FEW!] days and you'll be able to control them.