How do you stop colors from running in the wash?

I am in the process of making a quilt and I didn't pre-wash the fabric's before cutting, so I was wanting to know the safest way to wash them once I have completed the quilt. The fabric's and thread are all 100% cotton and the colors are creams, browns and reds. I know it would have been better to pre-wash first so please don't tell me that... but I started cutting the fabric's in a hurry.

Use ALL cold water..Wash & rinse cycle..use a mild detergent, and last but not least~ (Here's the secret:) add a cup or two of salt! I read that years ago about it helping jeans not to fade and to hold their color. I know there are some "color stay" detergents available now too, but I'd throw the salt in too! Good Luck! I hope your quilt turns out beautiful..you have alot more patience than I do:)

wash with cold water

Cold water, maybe even some sort of delicate setting.

Cold water wash and Cheer detergent.
I think Rit, and probably some other companies, also make something that you can use to absorb color from the water before it sets back into the fabrics.

Wash stuff in cold water if they are bright colored.. as in red .. blue .. Wash other whites in warm.

wash your darks and lights separatley. and hot water makes colors run.

I would say to wash in cold water and Woolite (if that product is still on the market) or a mild baby laundry soap.
The quilt sounds beautiful. One of these days I would like to make one.

Wash in cool or cold water with Woolite -
Not hot , nor warm . . . and no harsh detergents.
There may still be some bleed but they make a washer sheet that is suppose to absorb dyes in the wash.

cold water and a gentle detergent such as woolite will help to keep your colors from running. make sure to rinse the quilt well so that if the colors do run, they may not stain the cream. good luck :)