There was a time when several of us made an attempt to put out instructions for making better pieces, helpful hints, etc. unfortunately SNY's link is dead. Even when the links were active I'm not sure they helped much because newbies tend just jump on and patchwork a 3x3 quilt. The quilt look is what drives most veteran Gridheads nuts. Every once in a while someone works the quilt in a new an interesting way, but mostly it destroys the hard work of others to work collaboratively and drives other players away.
If you can play your squares and make the squares disappear you are doing a great job and more people will want play, if your pieces make the grid look like a visual tic tac toe or your grandma's quilt, more than likely people will stay away.
If you follow the threads here in the archive you will find a lively discussion from the middle ages of SITOland as well as several veteran gridcosm articipants opinions and suggestions.