Squash bugs overwinter as adults under plant debris, soil clods, rocks, log piles, and the like, so garden clean-up and removal of debris is a good start if you've not done that already.
Here is our page on squash bugs with a variety of ways to prevent and control them:
https://extension.umd.edu/resource/squash-bug-vegetables/

And here is our page on summer squash, with lots of great information on how to grow and care for them, as well as how to deal with other common pests and diseases you might encounter: 
https://extension.umd.edu/resource/growing-summer-squash-zucchini-home-garden/


Christine