Well, if you must know LOL! I'm a teacher.
During my education I learned how to research what interests me and then do it. I've always wanted to color my own hair because it was so frustrating to not get the color I liked. I decided to try it myself.
Basically it's not rocket science, here's a few tips.
1. Learn what your natural level and tone is--don't go more than two shades lighter with single process color.
2. Don't use a highlift unless you are a natural level 7 ASH hair.
3. Always bleach if you are a level 6 or darker to achieve any shade desired that is lighter than two shades your natural color.
4. Color won't lighten color--use colorfix if you want to change from a darker shade to a lighter shade
5. NEVER, NEVER overlap bleach. –Hair can usually be bleached about three times before it melts
6. Understand the color wheel and that coloring hair is basically like using water colors.
7. Find the correct products to baby damaged and dryed color treated hair, just cause the bottle says it works doesn't mean it's so.
8. STRAND TEST--need I say more 
9. Learn what PALE YELLOW (inside of a banana) and YELLOW (outside of a banana) mean. (I think people don't bleach enough sometimes)
10. When bleaching--bleach swells, make sure it's spread thickly and evenly on hair, don't let it dry out, use off scalp for highlights, on scalp for full head bleaching, colorfix prior to any bleach job, let hair be dirty a few days prior to bleaching--to condition the scalp, never use any higher volume peroxide than 20 or 30 when bleaching, bleach lasts for up to 90 mins--AS LONG AS IT'S WET--tone hair that has been bleached.
11. Find a shade you like and stick with it, if you want manageable hair.
12. Never pull through single process color to the ends...only use a demi or semi to refresh the midsection and ends when necessary.
13. Find a brand of hair color that you like and stick with it
14. Once hair is damaged there is no way to FIX it
15. Hair grows—thank goodness!