For the West Block, drive south from Swift Current to Val Marie, then follow the signed roads into the park. Parks Canada notes that the Ecotour route alone is about an 80 km round trip from Val Marie, so fill up before you leave town.
For the East Block, approach from the Wood Mountain side on Highway 18 and follow the signed park access road. The two blocks are far enough apart that it is better to plan them as separate outings unless you have more than one day.