At home hair coloring can be a little tricky, especially if you're attempting it from box coloring. They usually come in a single use foam or paint like texture. The foam texture is suppose to be easier to use but you can get an uneven coverage if you have lots of hair. After the choosing the type of coloring kit you want to use for at-home dye job you have to choose the color. Many people have an idea of what they want but most of the time reality and expectation is different. My advice is figure out your skin tone and determine if you should go for a cool, warm or brunette tone.
After this you can alway add highlights if you want more dimension.