
The most simple way is just dumping your PCB into irontrichloride in a flat bowl.
Etching accelerates with a little mechanic help. This can be done by causing the liquid to make small waves on the surface. Advantage: You can see the progress and take out the PCB early enough to prevent under-etching. Disadvantage: You have to do this for about 30 minutes.
2. Use a container high enough not to spill the chemical stuff. Then use a rotary type aquarium pump and a spray bar (Poke little holes into a plastic hose) and spray equally over the entire board. Either oscillate the board or rotate the plastic hose at moderate speed to cover the sprayed area all over your board. That works faster than the above described method.
HtG