How can i shrink a sweater ? the sweater is 55% cotton and 45% polyester , i saw it at the...

the sweater is 55% cotton
and 45% polyester ,

i saw it at the mall and that be the only size they have ,
so i had to grasp it one size bigger :(

how can i shrink it ,
without diminishing the color ,
it is a dark blue !

gratitude (:
Answers:    heat will shrink it. you could dry-clean it in hot sea and then dry it.

GOOD LUCK!
rinse out it in cold river then put within the dryer-hope it fits