Placement of your monitors is also quite crucial.
For best performance, they should be at ear-level for your normal seating position when doing your monitoring work. This might be a big of a trick for creative speakers, as they probably don't have any kind of a mounting mechanism to get them at your ear level.
You might want to build some brackets for them if they do. You will notice a marked difference, particularly in the treble side of things if you have them so that they present sound at ear level.
They should also be placed at the corners of an equilateral triangle with the center of your head at it's monitoring position. Some folks will point them at the head location, some do not. I'm in the former camp, but I don't have strong feelings either way.
I do feel strongly about laying monitors on their side or on the console bridge - neither should be done - plain and simple. Since you don't have a console, don't worry about this point - but you should worry about placing the speakers at the intended vertical position. What is funny, is that you'll see all kinds of 'pro' studios with Yamaha NS-10 monitors laying on their sides, on the console bridge! Some of the argument is that if you can make that situation sound nice, then a more ideal situation will sound even better - I have my doubts.
Sweetwater has a great guide for monitor placement and why/why not you should place speakers in different ways.
http://www.sweetwater.com/NearField/-Scott