What percentage of my tips do I claim on a 1099 if I am a bartender?

All the tips you receive and are not shared with the establishment are reported on your Schedule C as income.

Are you really an independent contractor?  You make your own work rules and schedule?  The place you work is a client for your services and not an employer?

https://www.irs.gov/businesses/small-businesses-self-employed/independent-contractor-self-employed-or-employee

The tips are additional business income, the same as the money that the establishment pays you. You have to report 100% of the tips that you get, whether or not the tips are included in the 1099 that you receive. However, you include only the amount that you actually get to keep. Do not include amounts that you tip out to other workers or to a tip pool.