You've already done the hard part...finding the person you want to spend the rest of your life with!
Once you set your wedding date, it's best to contact a marriage commissioner as soon as possible. Every year there are "choice" wedding dates which are in high demand, especially during the summer months. Be sure to include the date, the location and the approximate time of the wedding in your email or phone message. I prefer to meet with couples in my home to get to know you and learn about your wedding plans.
The steps you must take in order to be legally married in Alberta are found at Vital Statistics: Getting Married.