I have a tutorial on making pcb's using the UV transparency method, on here some where I think.......
Any how, here's my tips......
Make sure board is clean and grease free prior to drawing pattern.
I make my Fecl3 up as a batch.......250gm of xtals/pellets etc to 500ml of water.
When ready to etch board, warm solution in microwave oven, 10 secs at a time til its warm( 40deg C )
Place board in suitable container with pre warmed solution.....agitate gently.rock to and fro, warm as necessary in m/wave oven to maintain temparature.....
Upon completion of etching, wash board, then plate with tin plate solution.