Turbo's route misses one of the nicest stretches which is Sideroad 4 between Walkers and Appleby.
I think it's a prettier route than Cedar Springs tho either is fine - trade off on the way home. -
I would come up Snake then go past 5 to Parkside north of Waterdown - east to Sideroad 1, across Guelph Line ( there is a very hard right just before Guelph Line to take you down past some pretty escarpment and cross Guelph line there )
see the detail here of that very hard right. You can see you turning right down the escarpment - gorgeous property on the right as you descend.
this map below is slightly off.....
(Ignore that blue bit towards Kilbride - could not knock it out.)
Side Road 1 to Walkers ( some nice up and downs ), left to Sidreoad 4
this is the corrected route to Sideroad 4 - ignore the blue to the left - turn right just before the golf course, hardly looks like it goes through but it's truly lovely (
take it easy - sand sometimes and its a quiet rural area lost in time )
, right through lovely little stretch ( the turn is just before the Golf course - easy to miss ) to Appleby, north up Rattlesnake ( very tight hairpin ) then to Steeles that way.
If you are going both directions then you can go up Appleby on the way home, pick up Campbellville road at the 401 then west into - Twiss and some other good side roads a bit further west or down via Cedar Springs tho the top end of Cedar Springs is tricky to find your way.
Taking Britannia to Cedar is great but careful of the intersection there , up hill, off camber and cars tend to move fast.
OR
You can get to Snake again and take the first right going south after the twisties and follow the route laid out over to Ancaster and Old Ancaster Road after crossing HWY 6. Another pretty and enjoyable route with some superb views.
There are a lot of good variations that keep you off the slab.