I've been from Saskatchewan west.
There's another option besides the TransCanada and the Yellowhead and that's heading due west out of Saskatoon thru Kerrobert, Lacombe and Rocky Mtn House onto the David Thompson Hwy.
Then head up to Jasper and over Yellowhead Pass. You miss Banff Townsite - yeah! - but get most of the Icefields Parkway. Nice towns, local & provincial parks for camping.
Best - J