With tube tires there's little you can do to avoid goathead flats other than to avoid routes where they're common.

I used to use Continental Gatorskins, and one time had five distinct goathead flats on the same 17 mile ride. After that experience, I switched over to GP 4000s-II tires because I figured if I'm going to get goathead flats either way, I may as well enjoy the ride.

Bring a good mini-pump, bring a patch kit, bring tire levers, and bring an extra tube or two. You're going to get them. Best is to just be prepared for them so that they don't ruin your ride.