The following is compilation is not composed of all my own personal notes. Some notes are revised or copied from guides and posts/reposts from this forum but have helped me personally get through the learning curves. I'm no pro and not a genius by all means but what's helpful to me might be helpful to others too.
Just so you get a little idea of me, I started not flexible AT ALL, no real previous breaking experience, but a good strength/size ratio (as in i can lift myself up, do a lot of pull ups, etc).
Anyways, cut to the chase. So... I'll just cut and paste, kinda messy but I'll try to organize it as much as possible.
Stretching exercises
It DEFINITELY helped with mills, remember I was inflexible, and by that I mean I couldn't touch my toes without farting.
Leg stretches
Wide leg stretch (just go straight down, sidesplit) * Front leg stretch (both legs, just bend one knee and stretch the other one straight and switch)
Sit split (do the splits while sitting down and lean forward)
Sit stretch (bend one leg and extend other and lean into the stretched leg, then switch)
Stand up stretch (touch toes first then try to bring head to knees)
Back stretches
Cat back (kneel and put hands right in front of knees and bend back into a circle as if you're trying to touch the ceiling with your back)
Back stretch (lay down face flat and lock arms out to stretch your back backwards)
Back twist (put one bent leg over the other and twist in opposite directions, i.e. if you have your right leg bent over left, twist to the right)
A helpful note on stretching is that there's 3 main types of stretches:
Dynamic: Like kicking up as high as you can, a muscle movement which involves stretching
Active: Holding a stretch
Static: Holding your leg out and holding it (like some van damm move)
You should do dynamic stretches BEFORE milling and do active and static stretches after.
You can pull muscles if you do too much active stretching before any exercise.
Hold stretches for approximately 15-20 seconds each and it should sting a little otherwise you're probably not stretching.
Try to stretch everyday a little before and more after.
These are made-up names for stretches by me.
First couple days
Learn hand glide (I did some cricket practicing, my wrist got sore but this helped balance and wrist strength a ton).
Starting the collapse
Lock right leg out when starting.
Stay low to the ground and keep momentum parallel to the ground.
Turn and lean towards your left to bring right leg up, don't try to just bring right leg up, it can't happen.
Swing left leg under as hard as you can towards your right arm and then hold high to keep rolling on upper shoulders.
Spread legs out far as possible LOCKED OUT.
Roll hard as you swing left leg under (which is why you see some people bounce).
push with your offhand.
To the stab
LOOK where you're stabbing, and stab early, keep head down and hips HIGH.
When you get towards your front for the stab, stay HIGH on the right shoulder while stabbing with your left and pushing with right forearm.
Push with your free hand when re-stabbing to roll over the stab arm.
Kicking mistaken for swinging. just swing hard. kicking is related to bending your knee and you want to keep them locked.
Kick your legs as soon as your stabbing hand touches the ground (wasn't completely sure on this, feels like one smooth motion later but i was watching a mill clip in super slo-mo and it seems like a logical explanation).
Pull FORWARD with free arm to turn your body when in stab.
hold right leg up.
These 3 stars stuff was what got me through some mental roadblocks
Stab hard, don't fall on the stab, if anything think about not letting your body touch your stab.
LOOK WHERE YOU'RE GOING, YOU CANNOT TURN YOUR HIPS AND EVERYTHING WITHOUT YOUR HEAD LEADING YOU.
Kick left leg toward YOUR LEFT and some forward and right leg toward YOUR RIGHT and some back (in general), not necessarily up and down... What i mean is, LEFT is LEFT, and RIGHT is RIGHT not in relation to ANYTHING but your own body. (in relation to the ground it'll be to the side or up or whatever you need) i found the forward and back to be less important to me than left and right, which is why i capitalized.
Random notes to help clean up my mills and checklist myself, if i wasn't thinking or doing one of 'em, it was probably messing things up
High on shoulders
Torque hips
Keep hips HIGH
Keep legs straight and locked!!!!!!!!!!!!!!!!!!!!!!!!!!!
Push HARD
Stab EARLY
Torque more with your hips, go faster
UPPER BODY first into stab, LEGS FIRST out of stab... That's windmill right there - Pommy or someone (sorry if I misquote)
Rotate on shoulder blades to get the right leg under clean while split
Left leg towards LEFT and UP on the first rotation and every rotation to get right leg under
Pull toes up, easier to lock legs
Don’t look down, look up (look where you're GOING, not behind you or you'll slow down)
2 swings occur: the swing with left leg forward and under and then the right leg backwards and up
Hope this helps, I think that if you can checklist your way through, you might find it handy and help you past some blocks to your motivation and improvement.
Last note to people like me who have/had temptations to give up (in anything, not just millin of course):
10% inspiration, 90% perspiration (and bruises, and cuts, and just plain out banged up) - Joe