The 100 second @AlexM is a routine that the guy at Low End University created for himself to use before shows and recording. I can’t explain it all, but we can improvise.
First, you stretch each finger, 1 at a time, including the thumb, for 4. seconds each.
Do this by putting your finger up like this
And pushing back, towards the back of your hand. Go as far as you can, but don’t hurt yourself.
Do the same thing to all 4 fingers at the same time, pushing towards the back of your hand.
Hold it for 5 seconds each hand
10 seconds / 50 total
Bend your wrist and hand cowards the inside of your forearm like this
Then pull on your fingers towards your arm for 5 seconds each hand
10 seconds / 60 total
Next massage your upper fore arm here
with your thumb towards your elbow, get that muscle good for 5 seconds each arm
10 seconds / 70 total
Next massage the inner side of your arm here,
same area by your elbow , just the opposite side for 5 seconds each arm
10 seconds 80 total
Next, roll your wrists in full circles starting with your finger together like thr beak of a bird, like this
As you get half way around open your fingers full wide stretching as much as you can, like this
and as you get back to where you started, put your fingers back to the starting position.
Keep rolling, slow, but not too slow, opening / stretching and closing to starting position. Do this for a total of 10 seconds, you should be able to get about 4 full wrist rolls.
This should be one continuous fluid motion, not moving half way, opening hand, move half way closing it.
Just open and close as you roll, making sure you feel stretching in your wrists and fingers.
10 seconds / 90 total
Lastly, let your arms and shoulders drop, fully relaxes, and just breath in and out, deep breaths, completely relaxed, letting go of all the stress for 10 seconds.
10 seconds / 100 total.
You are done and free to play.
I hope this helps and makes sense.