You want to know how to do "what"?

[Jim_H]

FWIW, I like to cut my unwound strings a little longer than he shows here in order to get a few extra wraps on those. This ensures no slippage and pushes the string down for better break angle.

YMMV

Also, if you are going to pre-cut, make darned sure you are cutting the right string for the matching post. If you cut too short, well, its just bad.. don't ask how I know this ... :p

Edit to add:
Next time you are ordering from stewmac, toss one of these ezwinders in for $5.
http://www.stewmac.com/shop/Accessories ... inder.html

I chuck one up in my little Ryobi 12v cordless variable speed drill.. its small and light enough for the job and being variable speed I can go as fast or slow as I want.

[Jim_H]

Tony,

Read my last post :p $5 gets you the little ez winder attachment you can put in any cordless screwdriver :p

[seanbig]

Dave,

I will change strings one at a time occasionally. One instance is if the set of strings is fairly new and I have broken one of them I only change out that string. Another instance would be if I have a saddle that is not glued in, I'll leave the two outside E strings on to hold the saddle in place while I put the middle four strings on. Similarly, I will string up my banjo in the same manor because the bridge is not attached to the drum head. If you remove all the strings you may need to change the intonation of the bridge if it moves.

I don't see how it is possible for a guitar to break by removing the strings; you're taking the stress off the instrument. I suppose if the guitar has been strung up for a hundred years the wood could change shape? Then when you removed the strings it would put stress on the guitar? I don't know, it just doesn't really make sense to me. I'm sure there is a case were taking the strings off could put more stress in a different direction than the guitar is used to, but I don't see any normal case where taking the strings off would do that.

[Ken Hundley]

I suppose I would be more concerned with sudden string tension changes, like snipping a few strings at a time. (Golly, who would ever have done something so stupid?)

[Jim_H]

Yea, i'm always wary of using cutters to cut strings under tension.

I always loosen them up and gingerly cut them one at time, near one end (usually the nut). I've also been known to put a capo across them to keep them from flopping around.

I had a grimy B string snap and bury itself in my wrist once a long long long time ago. Fortunately, other than smarting for a bit, I came out a little wiser, but otherwise unharmed.

[Ken Hundley]

I just unwind them and pull the string from the post. Doesn't take more than a few seconds to totally unwind it.