Bleaching your own hair at home is decidedly risky. You may end up with uneven tones of orange and yellow, darker spots that weren't saturated enough and missed spots. There are a few ways to correct this. If possible, bite the bullet and go to a professional colorist and stylist for help. If you want to do it yourself, an at-home toner kit helps to smooth out the uneven color, or you can try dyeing to another color a shade or two darker to even it out.
Wash and deep condition your hair. Leave the deep conditioner on for about 15 minutes to saturate and moisturize the hair before putting any more color products on it. Wait a day or two for hair to recover from the bleaching.
Go to the beauty supply store and choose a toner with a purple or blue base to counteract the yellow and orange tones. Pick up a 20-volume developer and an applicator bottle as well.
Mix up 1 1/2 ounces of toner with 3 ounces of developer in an applicator bottle. Apply to damp hair, covering it completely. Leave in for no more than 10 minutes. This tones down any unwanted brassy colors and levels out the varying light and darker colors.
As an alternative to toning, choose a dye one or two shades darker than the color you have now. Apply the dye on the lighter spots first and leave on for 5 to 10 minutes before putting the dye on the rest of the hair.
Be sure to use a deep conditioner once or twice a week, and get regular trims to tame split ends.
To prevent hair damage, take a rest on heat styling during this process.
If the above methods fail, see a professional colorist or stylist.