This is my methods, and may not be the best to cleaning the stardust and Vision Extreme (which reminds me, i need to look to get more of those)
please be advised this is my method, and my not work for you. Sadly i have to add this warning tag and say that i assume no liablity for damaged/broken equipment this may cause on you.
Stardust: put about 0.8ml of water in there, then with the cap off put your finger over the top and shake the

out of it, then gently tap it upside down in the sink. Do this a second time.
If you have a darker color juice you will see the wicks turn white
then put it on a ego battery (if you have one), with a towel on your knee, gently tap the top metal ring on your leg, this loosens and removes water left behind in the stardust.
Now, with the cap still off blow into the star dust, then press the fire button on the ego, if your ego has a 5 second cut off great! If no cut off then count to 10 and release the button. Blow into the stardust and repeat this process until you see the wicks are dry OR you are getting a hint of smoke from the top needle. At this point put in the new juice. yes it will take a few pulls to re-prime the star dust
WARNING: by blowing into the stardust, water and residual juice will blow into your face, make sure to wear glasses that sit close to your face, like sunglasses
The Vision extreme: I have a glass i have deadicated to cleaning the extreme, clear smoke tech dual coils, my drip atty, ego-t etc. What you do is drop the extreme into the glass of water....i let mine site in the water for 24hrs, then take it out via strainer and sink, blow into the battery connection end to remove water, put in a open window and let it dry 24~48 hours
Again this is my methods, which again may not be the best and there could/would be better ways, hope this helps