By far the easiest way to get around is by vehicle. Vehicle rentals are available in Calgary, Banff and Lake Louise.
It is also possible to cover the park on bicycle, but keep in mind the mountainous terrain will make this quite a workout. Bicycle rentals town, road and mountain bikes are also available with in Banff and Lake Louise, visit the Parks Canada information centre for both road and trail routes.
Or rent a moped from Bactrax/Snowtips (http://www.snowtips-bactr...) to explore the area around Banff!