Dig a hole about 3 times as deep as the size of your bulb. If your soil contains a lot of sand, you can plant the bulbs a bit deeper.
If your soil is heavy clay, try adding some Gypsum soil conditioner ( comes in a 5lb bag) to break it up, add some top soil.
If you can't plant your bulbs deep enough, then rodents can find them...and the bulbs will make their way to the top above soil line.
Follow the bulb grower's instructions on the package or box.
Make sure your newly purchased bulbs are still fresh. If you can press all the way through it, don't buy them.
Plant them " pointy side up" Roots grow from
the bottom. Space your bulbs far enough apart so they don't touch. Crocus can be planted a little closer together, for example. But Tulips, Daffodils require more space. Common sense.
Feed the bulbs with bulb tone, bulb food etc. You need the bulb to form layers in the winter as it's growing deep in the ground.
Fill in with soil, water well and mark where you've planted. New growth sometimes looks like weeds, you don't want them pulled up by mistake. A plastic stake is best, not a metal one.
Mulch the ground, making sure the bulbs are tucked in nicely through the winter. Make sure they are planted in a sunny spot, no sink holes that hold water ( a low wet area in your yard)
To keep squirrels away, you can try placing a thin wire mesh around the base of newly emerging tulips/ bulbs. Or, place a tarp, blanket or heavier cloth around the bulb during winter. Just remember the bulb needs room to emerge in spring.
Most bulbs need to be thinned out
over time. Think of a clove of
garlic, and the little "bulblets"
off the side of the main bulb.
They need to be separated into
their own hole at some point
so they don't crowd the Mother Bulb.
You can leave them alone if
you wish, but overcrowding is not
good for bulbs.