2 big things to worry about are the smell and red eyes. Use a redness relieving eye drop before you smoke and try to keep the smell off of you (like not smoking in confined spaces) in addition to covering it up from using perfume or colgne to washing your hands well to what is one your breath. Next, if you are a new smoker you will need to try to keep from giving yourself by not getting so high that you make a babbling fool out of yourself. Everything in moderation! Finally, don't forget it is illegal for most people so don't get caught by the law. This is a surefire way of giving yourself away.

Storage is another concern as some marijuana can have a very strong smell without even being burned. Don't forget about your paraphernalia either.