|The main carrot bed, covered with Enviromesh|
The method is simple: cut the sticks to the desired height; push them into the soil/compost at appropriate points; place a cane-topper on each stick (without these, my thin sticks made holes in the mesh and poked through); roughly cut out a piece of the mesh and drape it over the sticks; secure it in place with a big rubber band; trim off any excess mesh. That's it.
I think I may have cut my sticks a bit too short, and will probably have to replace them with taller ones in a few weeks' time, as the carrots grow. Also I think it might have been better to use 2 or 3 rubber bands to secure the sticks to the outside of the pots. This way there would be less risk of damaging the little carrot plants. The Mark II version will be better!