Your key bindings

I always use 1-5 + space bar keys set up cuz I like play Invoker with legacy hotkeys :0
My active items will be on 2,3,4 and space bar since it's easier to reach them, and 1/5 will usually be boots/TP/non-active items...

WASD for camera (Yes...)
1-4 for abilities. If there are six abilities, then 1-4, Q and E.
R, T, F, V, C, X for items.

Abilities: R,T,G,Y,6, ult in H

Items:
Mouse 1 - Magic Stick in early, Blink Dagger if bought, basically items you have to be able to use quickly when needed
Mouse 2 - Power Treads, Phase Boots, and items you need to use a lot
4 -An item of not so high priority usage, items without actives, wards, smoke and stuff like that
5 - Scythe of Vyse or just something that is bought, and has an active
N -TP scroll, Bottle if mid, Force Staff
M -TP scroll if an item in N

Everything except N and M is set on quickcast.

Other stuff:
F -select hero
E -select all units
W -select all other units
Space -Stop
D -attack

First of all, my abilities and items are on quickcast.
Abilities are normal qwer bindings.
My items are bounded to Num4-Num9 ( Have a nice Logitech G600 with 12 buttons on the left side)
But for the items i dont have a regular order.
A = attack
Space = Stop
1 = Select hero
2 = Select everything except hero
3 = Select everything

I would advise to always put the courier on a hotkey. Usually I put hero on 1 and courier on 2.