Roots

They shouldn't be giving you orange roots. You can go to Sally beauty supply and buy a high lift blonde. Make sure you get one with a "drabber" or "green base". It will counter the orange that comes out in your roots. Be sure to buy 40 volume developer to mix it with, and a plastic bottle with a tip so you can just part your hair with the tip and squirt the dye on your scalp. Be sure not to pull it through your hair, just do your roots. The green base won't turn your hair green if you do, but it will give blonde hair a greenish cast that isn't so nice. All of these supplies will probably cost around $10, and you will be able to use the developer every time you do your hair for years. The plastic bottle can also be washed and re-used.

If your roots are very dark, you may need to do your roots twice if your blond is very light.

A word of caution. Doing your own hair is always risky...if you do exactly what I said, and do only your roots, not your highlights or other hair, you should be fine, but if you get tempted by other products in Sally, be aware that there's a lot of risk involved.