I also agree with ham_man. During my first several days of contact wearing, it took some time to get them in and out properly.
Also, don't be surprised if, for the first couple of days, you only feel comfortable wearing them for a few hours at a time. You might have to "build up" to wearing them for a full day.
Unless you have lenses that are designed to be worn overnight, I would not recommend sleeping with the contacts in.
Also, it's probably a good idea to keep your glasses prescription current and have a pair of glasses on hand. Wearing contacts when you're sick, particularly if you have watery or really dry eyes while ill, can be very uncomfortable (this is my experience, at least, and I've been wearing contacts for 13 years now).