Can off-the-rack clothes be tailored?

(2obvious)
snip
I wear a lot of T-shirts (very few button-up shirts). I'm willing to
invest the time and effort into learning how to tailor my shirts, but I
have no clue where to search for books or instruction. A cursory pass on
the Internet turned up nothing of value. Can anyone guide me in the
right direction? Is this even /possible?/
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Sure it is. It's called altering your own garments. If you start with
a couple of practice Tshirts, you'll be good at it in no time.
I've tailored both men's suit jacket shoulders (not my favorite thing
to do), and narrowed suit lapels.
Altering T shirts is a walk in the park, but I warn you--results vary
with the machine you use. I highly recommend using a serger to alter
knits.
Let me recommend :
'Altering Men's Ready-To-Wear', by Mary A. Roehr. ISBN# 0- 9619229-1-5
I picked up my copy at Joanne fabrics, for half price, and there's
always ebay, Amazon, Hamiltonbooksellers, etc.
Go to www.joannefabrics.com, and sign up on their mailing list. Every
month, you should receive a sales flyer in the mail, with a 40 to 50%
off coupon. NAYY.
Cea