Yes, although the preference is to complete preparations closer to immersion, if need be you can do your
chafifah early.
To the extent possible, try to avoid anything that might get you dirty and be difficult to clean off. You should avoid eating until after immersion, but drinking is permitted. When you arrive at the mikveh, you should rinse off in the shower, rinse out your mouth, comb your hair, and visually inspect yourself just prior to immersion.
Please write back with any further questions.
