Depth of Market

I'm looking for some guidance on the best material to read/watch on the depth of market, I have a free trial of software that analyses the DOM and puts it on a table and graph. I was looking at various companies last night and this morning and "thought" i was beginning to read strength and resistance on the buy and sell sides. Well i guess i was wrong as i entered into a trade today (small scale) thinking that there was an abundance of buys with sells not equally stacked on the other side only for the stock to swing into a down cycle.

Tempy