Drive by the bar at least once on a busy night if you’ve never been there before to give yourself an idea of what other people are wearing. While you might not wear the exact same thing as someone else, you can at least see the style of the bar. There’s nothing worse than showing up in jeans when everyone else is in formal wear.
Play up your best feature and favorite asset. If you love your upper body, wear a tight shirt that accentuates that area or choose a short skirt to show off your legs. As long as you’re happy with what you’re wearing, nothing else matters.
Wear comfortable shoes that have been broken in and worn at least once. As great as those new four inch heels might look, you’ll feel uncomfortable and tired if you’re not used to wearing them.
Choose clothing that is disposable. Accidents happen in bars all the time and you might ruin a new skirt or pair of shoes even if you act carefully. If someone spills a beer on your shoes or on your skirt you’ll be glad you picked something disposable and isn't irreplaceable.
Ask your friends for advice and turn it into a party. Invite your friends over before going out. Everyone can get an idea of what everyone else is wearing and give their advice on the best outfits.