Coloured markings
I decided to look into using coloured markers because of the limitations detailed in magnetic markings.
The idea is to use a label on the back edge of the base (so that it can be readily seen by the commander, but not by his or her opponent). The basic label size for squads size is 30 mm wide by 2 mm high, printed on paper, then glued to the back of the base and varnished for protection.
GHQ British infantry. Platoon commander and 2nd section from 2nd platoon, 1st company. |  GHQ British infantry. Forward observer and mortar teams from 1st company. |
I use three sets of symbols, indicating the company, the platoon, and the squad. I opted for this scheme as it emphasises the platoon, the key organisation in Crossfire.
- Company: thin vertical bands indicating the company number, in blue (German) or red (British)
- Platoon: wide coloured band (red=1, green=2, blue=3) (No coloured band for company-level assets)
- Squad: thin vertical bands indicating the squad number, in blue (German) or red (British). (Numbering also used for company assets, such as mortars)
I opted for this scheme as it emphasises the platoon, the key organisation in Crossfire.
For more details have a look at this file, which has the markings for three German and three British companies: unit markings. (The black and white checks are a guide to aid cutting).
There are, of course, many ways of coding unit markings. Have a look at Tim Marshal's pages for another way of doing this.