the most natural way for me is to use the CH-keyboard!
it offers °'^`~" independant from aeiouy and usable on each of them (minuscule or majuscule)
and éüàäöüç complete with the accent or cedilla
only the german ss is not available. germanophone swiss people seems don't to use it!
the CH-keyboard has 2 variants: fr and de but all the signs are the same
but the CH-keyboard is only available in Puppy using the dotpup for international keyboard
this keyboard don't work properly any more (since about puppy 2.10). at installation time you have the chance to start it and choice CH fr or CH de, but after that it is not possible to change again (in Puppy 2.02, you can change daily or more). but it is not a big problem: CH is the most complete keyboard and it works very properly in puppy 3.0 beta