I recommend you to read the pdf file in Beginners Guide 2 Dual-Boxing (3,4,5 boxing) , helped me get it up and running in notime! AND I had a epic hangover when I did it

Im a really noob in multoboxing myself, but I've spent hours ingame to config my keys to get it to feel right for me. Dont think theres a general solution to this.
And as you level, theres are new skills and macros to config, so it's pretty slow so far :P

Buw check out the Wiki, theres some good tips in there about macros etc.