I used to perform bar magic and have a couple of suggestions.
First, be a damn good bartender and always pull your weight.
If you are working the day shift and the happy hour bartenders come in and run out of juice etc., they will begin to hate your magic.
The rule GTFM always applies. Your number one job is to put money in the register. If you are in the middle of a trick and someone (customer or wait staff)wants a drink, make the drink before finishing the trick.
The customers might like your magic but the opinion of your co-workers will pull a lot of weight when your manager decides the schedule.
Since you are new to bartending, I would suggest looking for a day shift somewhere. The lunch rush will give you the experience you need to build up speed. You can come in early (don't clock in too early though)and get a jump on setting up the bar to allow more time to perform for bar customers and still have the bar ready for the Happy Hour and night shift.
I wouldn't do magic right away. Learn the bar. You need to be fast and efficient. Know where everything goes and learn to use both hands at the same time for different tasks (put in mixes, straws and garnishes while pouring with the other hand.
Learn to memorize large orders so you can set up all the glasses and go to it all at once.
A good bartender is fun to watch. You will have a ready made audience to perform for.
Learn quick, visual tricks and sight gags that you can do while busy w/o slowing down ie: when giving change, transfer quarters from RH to LH (not really) and when your left hand reaches across the bar, let the coins fall from your right hand onto the bar. The sound illusion is perfect. The customer reaches for the coins as you move your LH away and they aren't there. Before he reconstructs, move your RH revealing the coins and go back to making drinks.
When its slow, you can do longer tricks but don't get annoyed by interuptions, you are always a bartender first.
Share the rewards.
If you work with other bartenders at the same time, I suggest splitting whatever tips your magic brings in and let them know it. They will be stoked when they see you get a $20.00 tip and add it to the jar. They will also be more tolerant of you performing while they stock beer, make drinks etc.
Try to find a bar/lounge/restaurant that fits your style. Its hard to imagine Jim Patton and Bob Sheets working the same bar.
You may have to get some experience before getting a job at the place you really want to work. Talk to managers (before 11am and/or between 3pm and 4:30pm.
Be persistant. Say for instance: Hi, My name is
Adam Brooks. There are over four hundred restaurants within 20 miles from here and this is the one I see myself working at. Why? It fits my style. I'm an excellent bartender. I'm fast, neat and dependable. I get along with just about everyone including customers and the rest of the crew.
This seems like a fun place and I think I would fit right in. When its slow, I can perform expert(professional etc) sleight-of-hand that the customers really seem to enjoy.
In fact, I have a couple of tricks that are specifically designed to get the customer to come back with freinds. I'd be more than happy to show you when you have the time.
If the answer is not right now, ask if its OK if you check back in a month. Then keep checking once a month always by stating your name. Eventually, the manager will remember your name on his/her own and will hopefully decide to give you a try.
When you do get a chance, prove yourself as a bartender before you get carried away with the magic.
Hope that helps,