Here are a few general tips on the rack.
Check For Frayed Wires
Check your small brass wires for wear and tear just below the head. These will, and do, snap if they are frayed. Check the trigger wires on your cams for fraying, whilst not fatal it can be difficult placing and removing them without a working trigger bar. (So be afraid of frays!)
Don't overload your krabs with wires. Any more than six or seven per krab and it's difficult to extract the wire you require without dropping others.
Take A Variety Of Draws
If you are trad climbing you will need a variety of quick draws, long, short and medium. It is useful to have some of variable length too, for example a 120cm sling can be used doubled, trebled or as one. Try carrying a couple of medium quick draws with 'revolver krabs' on as these can really reduce drag on long pitches.
Try carrying a 240cm sling and two or three of the modern thin 120 cm slings, you'll be amazed at how useful they can be on small spikes, threads and for tying off dubious pegs.
Rack To Sack
To put your rack in your sack don't clip it all on one sling, this means it comes out in a right mess. Clip your krabs carrying wires together, then place them in your sack. Clip your quick draws together then place them in your sack. Clip your cams together then place them in your sack and so on until you get to your slings which you can hold together then tie them in a loose knot. You'll find removing your rack form your sack then racking up a much smother operation next time you go out.