A fan brush, cotton ball, gauze pad and Q-tip can all be used, but it really comes down to personal preference on which is the best for you.
Fan brushes are excellent for applying to someone else, but can be tricky at first for personal applications.
Cotton balls and gauze pads have a tendency to soak up a lot of the peel before it reaches your face. Cotton balls also have the added disadvantage of coming apart in male facial hair.
Q-tips are mainly for spot treatments. Trying to do a full facial peel with just Q-tips will take a lot of time.
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