Are you familiar with blanching vegetables before freezing them? If so, blanching time for sliced summer squash is three minutes.
If you are not familiar with the process, Google "freezing summer squash" and you can get pretty detailed directions. It is really not hard.
The problem I have with freezing summer squash is that they lose texture and become pretty mushy. A lot of people really don't like that. But I find that some frozen squash make a good change of pace in the winter when everything is coming out of a can or the freezer, even if they are mushy. And they can be added to soups or stews pretty late in the cooking process. Again, they are mushy, but in a soup, it does not matter that much.
You can pressure can summer squash but those are even more muchy. I certainly do not recommend canning them but prefer to freeze.
After freezing, you may want to drain the thawed squash in a strainer and even pat dry with paper towels to remove excess moisture. Then you could use the squash in a baked casserole, rather than eating just plain. At least that is what I would do.