Encourage biodiversity in your garden. A plastic drinks bottle with the bottom cut off, stuffed full of rolled-up corrugated cardboard and hung from a tree branch gives lacewings somewhere to shelter. A solid block of wood with lots of 1/4" holes drilled deep into it can help overwintering solitary bees. A few logs piled up somewhere can provide havens for ladybirds and all kinds of other beneficial insects. Feed the birds, too. The more kinds of living things in your garden, the healthier it will be. I still kill slugs, though. You've got to draw the line somewhere.
This tip kindly donated by Melanie, BEANSPROUTS