I want to use professional hair color at home, Any advice? I don't want my hair to fall out.?

I know this much: I was thinking Redken Shades EQ or Wella Koleston. I know it needs to be mixed with developer (20Volume?)-but, is it that simple? and do I need a certain brand developer to mix with a certain brand dye, or does any brand go with and developer? Also, what is the ratio of color to developer? I have light brown hair, am looking to dye it to dark brown. THANK YOU!!!!!I want to use professional hair color at home, Any advice? I don't want my hair to fall out.?
Be careful with your color choice as 'dark brown' could be REALLY dark brown. It's better to choose a shade or 2 lighter than your desired color. I use a 10 volume on my beautician's recommendation. The lady at Sally suggested a 20; think it depends on the hair. Usually color is mixed 1/2 %26amp; 1/2 w/developer. It really is easy to do. The hardest part is deciding on the shade. I've had very good luck w/Nice %26amp; Easy, Revlon, %26amp; L'Oreal brands, too, from W-M, etc.; everything you need is in the package. If you go to Sally, there should be someone to help you find the right products.