Slugs and snails love yeast, so it makes a great, child and pet friendly means for dealing with them in your garden.

[edit] Steps

Put a lump of brewer's yeast or sprinkle powdered yeast into a jar of warm water and sugar.
Dig a hole large enough for the jar to sit in up to its mouth . This is best done in the vegetable patch or other garden space where the slugs and snails are patrolling.
Check daily and remove slugs and snails that have been attracted to the jar and dispose of them. If you have a very large garden, you may be able to simply put them in another area of the garden.
Renew the mixture regularly. It will be impacted by rain and evaporation, so top it up as needed.