Growing Avocados from a Seed

My mom lives in San Jose Ca and started an avocado tree (years ago) from seed by putting it in a jar of water (with the seed held up by toothpicks) on her kitchen window sill. It's now a full size, fruit bearing tree in her back yard. Me, I'm in Co and I can't even get the seed to grow roots. I've tried several different ways and still no luck! The green thumb gene obviously past me by!

I have had great luck wrapping the pit in wet paper towel and putting in an open plastic baggy and putting under the dark sink cupboard for a couple of weeks and it is ready to plant in soil.

Put 3 toothpicks in avocado, 1 on each side, so the avocado doesn't fall into the glass of water, sit the glass in the window. The seed will sprout and grow. Maybe you can do a search on the internet to see how to care for the plant if you put it in the ground. You can use it as a house plant by potting it in a planter.