Many soil problems can be remedied by the addition of compost to your garden.
Compost is easy to make. In nature, things naturally decompose. But if you're in a hurry or want to generate high-quality compost, you may want to delve more into the science.
There are numerous sources on the internet about composting. Rather than create yet more content, we point you toward some good resources. Several Master Gardener volunteers are very experienced in composting. Feel free to ask us any questions about the process.
There are some local issues with composting, however.
In locations with lots of bears (Mammoth Lakes, etc.), composting is not advised. You will attract bears with food and edible debris. If you wish to compost food waste, consider using a worm bin inside.
Because our summers are hot and dry, it's important that materials added to the compost pile have moisture. If they do not, you will need to add some water. Not a lot: sloppy wet is bad. Covered beds will not dry out as quickly. Tarps or plywood work well for this. Be sure to secure them so the wind doesn't blow off your cover.
Winter conditions will slow down composting. Don't expect a fast process outside in winter.
Worm Composting Basics (Cornell)
Making Compost in a Hurry (UC ANR)
Composting for the Home Gardener (Sacramento Co. Master Gardeners)
Compost Home Page (CalRecycle) This is probably the best place for research-based compost information
Compost Calculations (Inyo-Mono Master Gardeners)
School Composting Lets Get Growing (Cornell)