Unless you mean judging distances on the map?

In that case I would probably lay out lines of floor tiles or beams of different lengths like 10, 25, 50 and 100 pieces and learn to judge it on the map that way. Same way you can learn to judge 1/10 of a mile from highway markers.

I tend to lay out my bases more organically and flow with the terrain. Build as needed type thing, so take what I say with a grain of salt. It's just how I would do things ha ha.