IC means nothing with preparation.

Put garrison divisions on your coasts, the more the better, and attach brigades to them (artillery usually works best, rocket even better, but that is for more powerful countries), then spend some IC and time to fortify them (1 or 2 fortifications are good enough, IIRC).

When you have the troops and are not at war with a neighbour, put army forces in reserve behind the coasts (I usually use 3 cavalry divisions with AC attached, mainly using them to subdue partisans).

Interceptor or fighter squadrons can also be of use, but rarely, it is good to keep a few on hand, of course.

Also, if you are in the Axis, then you can expect Germany to start dropping troops to your area and giving them to you. Happens constantly. Other countries probably will.

My current campaign with Germany has Argentinian troops seeing combat everywhere from Finland (beats me how they got there) to the Pacific. They are actually more useful that Italians.