Sanding on the ferrule on a LD shaft is a giant no no.
My point is there is no reason to sand on a shaft, if the shaft is dented then the dent is steamed out in a matter of 5 minutes. Solid maple shafts can be steamed, I wouldn't steam a laminated LD shaft .
If I want a pissed of customer, then all I have to do is sand on his shaft .
So would you advise not using the McMagic papers from McDermott? I used these to clean up my shaft when it started sticking before I moved to a glove. I hate the look of the glove but damn it keeps the shaft clean for a lot longer period of time.
As for the OP... I would love to change my own tip because I like to experiment and I was in your shoes a few years ago when I didn't know anyone to change tips for me. I was stuck changing once a year because there were always repair booths at the tournaments I shoot.
Then I just asked the owner of the place I shoot and got a couple names and lucked out my first attempt and got one of the best. It does cost a little more to have someone do it for you but I don't trust myself enough to do it on my own. I like my cues pristine and I'm nitpicky enough that if I scratched my ferule at all I would have to have it changed. A buddy of mine sanded the crap out of his ferule exactly like the one MortuaryMike posted and it drove me nuts to even look at it lol.