On a walk it is highly recommended that you bring something in your mouth, either to chew, or to work, or simply to have on hand in case of boredom or other emergencies. Do not worry if your jailer removes puffy toys and tennis balls from your jaws before you set out; you can always pick up something along the way.
Here are some things that have worked well for me:
sticks (Note: Sticks are primo! They're the best! Including the really long ones that are three times my size and which get caught between trees!) (Note: Sticks can prove so primo and so distracting that you might find yourself lying down in the middle of the walk and chewing away, blissfully. I say, worry not. Go with it.)
mittens. usually one, snatched off the hand of your jailer. heh heh heh makes em nuts.
small bits of gravel
lumps of dead grass
clods of dirt (Note: "Clods" is a great word. I learned it yesterday.)
mulch (Note: this works best carried entirely inside the mouth. Also, if you can't find any, I know a good spot on Argyle Street where you can get some.)
whatever contraband you can find: bits of wrapper, dead balloons, plastic sacks--you know, anything edible and tasty. (Note: The jailers will almost certainly take these away if they notice. Be sneaky.)
and the best thing of all--always there, nice chewing consistency, good flavor, always drives the jailer nuts--THE LEASH.
And don't forget: When you get home, trot into the house, get a big slurpy drink of water, and then jump on your brother's head. That's what I call a good outing.
Cheerio! Over and out!