Commonly used dosages and durations include:

For treating fungal infections of fingernails or toenails use 100% tea tree
oil twice a day for 6 months

For treating athlete's foot use 10% tea tree oil twice daily for up to one
month

For acne use 5% to 10% tea tree oil once a day indefinitely

For oral candidiasis use one tablespoonful of 5% tea tree oil solution as a
mouth wash taken up to 4 times a day. (Make sure to spit out)