Don't through away your ladybugs this spring via over-enthusiastic raking and clean-up. Instead, rake the lawn or garden lightly and gather up the materials and start a pile of leaves for future leaf mold. This is not the same as compost.... it is a dryish pile left somewhere on your property that you can get to later to use in the compost or not. This way the wakening ladybugs will have a chance to warm up and fly off to breed.
Thanks to Joan for the great photos of the ladybugs breeding!
PS Waking ladybugs need to eat and there probably aren't any aphids out yet so allow some early flowers to be their pollen source.