Help! I found a turtle nest !

Here are some options if you find a turtle nest and are worried that the nest will get destroyed:

Make a chicken wire mesh and put over the nest site, then ignore and see whether turtles will hatch. You can make a wood frame to make it sturdier and keep the dogs and other predators away from eventual hatchlings. If this is in a lawn, don't mow around the nest, and don't walk on the area.

Relocate nest. This is tricky, since turtles eggs should not be turned over once layed. Also, picking a good nest site can be tricky, too. You'd have to take out the nest with quite a bit of dirt, and then "repot" it at the new site. However, if you think this will improve the turtle's chances, why not give it a try. Pick a site that does not soak, drains well, does not completely dry out, gets some sun, and make sure you don't turn over the eggs during digging and transport.
Do nothing. This sounds heartless, but only a small number of nests survive predation in the wild, and only a small number of hatchlings survive to adulthood.
Instead of incubating the eggs yourself, find someone who would take them.

You can use something like this to make a protector.

Put a heavy brick or stepping stone on top, or stake it down!

Dig up, take indoors, incubate, then let babies go when they are a few weeks or months old.

Brand new nesting area for pond turtles.

These are good basic incubators for a decent price. I've had mine for over ten years. G.Q.F. Manufacturing 1602N Hova-Bator Incubator