When doing Botox, it is hard to say if you will bruise.  There area areas that have a higher tendency to bruise, such as around the eyes.  There area a few things that will help reduce the chances of bruising, but there is never 100% chance of not bruising.  Many times it depends on the injector, whether they are aggressive with the needle, or do they take their time to look for blood vessels.  Things you can do to help reduce your chances of bruising are – Arnica Montana is a great homeopathic drug sold over the counter.  I typically recommend starting Arnica 3-4 days before injections.  Avoiding alcohol for a couple days before any injections will also help keep your blood from getting too thin.  Do not apply numbing cream to the area where you are getting injections.  Numbing cream causes the blood vessels to become dilated and puts you at a higher risk.  Ice before hand can help, but I never recommend ice after Botox, because it will interfere with the absorption.  If you get a really bad bruise, IPL laser can help break down the blood and help it heal much quicker.