These guidelines are taken from the github page. I'm guessing you are talking about 1v1 arena maps (with the am_ prefix) for the 1v1 mod made by splewis. also breakables can help cause they indicate that somewhere has been there. And you probably start going counter clock wise about the time the other one is changing directions. just make sure your map is not 1 big loop cause if you both go clock wise then you never find each other. It should be small enough that you can here the 'knot' from everywhere inside the 'loop' (else you can miss each other). The inside of the loop should be playable.

(I couldn't find a better image to explain)

Instead of a dead end you can also create a small loop. The important thing is to have the dead ends playable. But in a LAN having 2 dead ends plays really well, cause if you go from 1 dead end 2 the other you have to meat your enemy along the way. Forget what they say about dead ends! Normally dead ends are bad in maps. Don't create a maze, keep the layout simple. Sound can be really help full to find each other. I used to have 2 pc's at home to LAN in the time my internet was to slow to play online.