Best way to KILL squash bugs ?

It's suggested not to kill them. Pesticides are not good but you can

• Remove or knock off and kill nymphs and adults by dropping them into a pail of soapy water. This is particularly effective if only a few plants are affected. This can be challenging because squash bugs hide under leaves and move quickly when disturbed.
• Crush eggs that are attached to the undersides and stems of leaves.
• Trap squash bugs by laying out boards or pieces of newspaper. Squash bugs will congregate under the boards at night, and then can be collected and destroyed in the morning.

Remove plant debris around the garden during the growing season to reduce the potential harborages where squash bugs may hide. Clean up cucurbits and other plant matter around the garden in the fall to reduce the number of overwintering sites.

Apply food grade diatomaceous earth and spray the plants down with horticultural oil

Again I went to the expert, Jerry Baker. In his Giant Book of Garden Solutions, he offers these two cures for squash bugs:

1. make a tonic of 6 cloves of garlic and 1 sm. onion (finely minced), 1 tablespoon cayenne pepper, 1 tablespoon liquid dish soap (no disinfectant added), and 1 quart of warm water. Mix and let set overnight. The next day, strain liquid into a hand-held sprayer GO know 'em dead!

2. to keep them away next year, use companion planting. In among your squash, plant nasturtiums, onions, marigolds, or tansy. They mask the smell of the squash plants AND squash bugs hate the odor.

Take care and God bless