I have 3 - all girls - 5.0, 3.4, 1.8.
DD1 has SN so goes to Special School, and HAS to be ready for her bus by 08.25. Non-negotiable.
DD2 goes to preschool and starts at 09.00.
They all wake really early (between 05.00 and 05.30), especially as DD1 is an early waker and noisy.
DD1 needs full help with dressing.
DD2 can do knickers, socks, some trousers, needs a bit of help with preschool t-shirt but can do buttons.
DD3 needs full help.
The key for me is not to do anything til the last minute - any earlier gives them the opportunity to undo what I've done!
I grab a pile of clothes for each of them, dress DD1 at 8.00 and do shoes, hair, coat, etc. Out the door at 8.25 when her bus arrives.
Then I either help DD2/dress DD3, or if I managed before DD1 left, they play for a minute or two. I prepare DD3's lunch.
Then it is a mad dash of 'treasure box toy, coat, shoes, hair, lunch box - let's go!!!!'
Take DD2 &3 to preschool, then come back and spend the morning with DD3 until 12.30 when DD2 comes home, and 15.30 when DD1 arrives home!