It's not difficult to change your hairstyle. Dyeing your hair from red to brown is an easy and subtle enough change that it won't require a visit to a local professional salon. Using a boxed dye will more than do the trick. It also will save you plenty of money. You should make sure you perform the allergy test listed in the instructions before you actually dye your hair to avoid an unwanted reaction.
Make sure your hair is dry, unwashed and stripped of all styling product. Put on an old T-shirt that you won't mind getting some dye on. Comb your hair out to remove all tangles and carefully part your hair into at least three separate sections. Secure each section with a hair clip.
Open the box of hair dye and put on the supplied gloves. There usually are two separate bottles to mix together and a small tube of post-color conditioner. Mix your bottle according to the instructions that are included with the dye.
Remove one hair clip, releasing a section of hair. Use the comb to help you evenly distribute the hair dye from root to tip. Dye the entire section, making sure the hair is saturated. Once the section is done, use the hair clip to once again secure it to your head. Repeat until all sections are dyed.
Place a plastic bag over your hair (not your head) and secure it with another hair clip. The heat from the plastic bag will cause the chemicals to react better to your hair, ending with better, richer results. Wait however long the instructions say, usually anywhere from 20 to 30 minutes.
Remove the plastic bag and all the hair clips. Rinse off all the dye in the shower. Do not use shampoo unless instructed otherwise, and don't stop rinsing until the water runs completely clear. Apply the post-color conditioner that came with the dye, saturating hair from root to tip. Wait for three minutes, then rinse all the conditioner out. Dry and style hair as usual.