DIY or Salon?

i can tell you from experience in the last couple of days, if you dont really know what you're doing or are unsure of anything related to your hair, you either need to consult a professional or let them do it for you. going darker shouldn't be to difficult, just go and get the box of color you want and follow the instructions to the tee. i like nice and easy cuz it's what it says. but if you go darker your still going to have to do the upkeep on your roots every six weeks depending on how fast your hair grows. i wouldnt stray too far from the natural color if you are tired of the upkeep. but you should successfully be able to cover the highlights, i've done it in the past without issues. just be careful how drastic you go, innevitably you are going to want to return to your natural color at some point in time. (i had dirty blonde and went burgundy then black, had to get all that out of my hair and had orange hair for a minute.) hope this helps some!