Starting out a pup

Most bulldog pups are ready to begin their early introduction to weight
pull around 8-12 weeks old.
By this we mean get them used to the clangs and bangs and sights
associated with pulling.  Load them up in their crate and take them to
where others are pulling (be sure their vaccinations are up to date). Set
them in line with the other dogs and their crates to watch what is going
on.  Sounds funny, but it works great.
After a couple of weeks doing this put a collar and leash on your pup
and add them to the lineup of dogs.  When it is their turn carry them up
to the track set them down at the end.  Give them a pat and tell them
let's go.  Walk them down the track (kids are great for this part).  
When you get to the cart turn them around (tell them turn while you
are doing this). When they are turned around tell them good
puppy/dog.  Then tell them to work (be very upbeat with them) and
walk or run with them to the end of the track.  When you get to the end
tell them whoa/wait (or ho whatever you use be consistent). Then pick
them up and praise them and love on them make a BIG deal of what
they just did.  Carry them back to their crate and tell them to load as
you put them in and give them their favorite treat. Praise them again
once they are in their crate.  Repeat this 3 or 4 times.  Keep the
sessions around 15-20 minutes.  Puppies have a very small attention
span.  You must make it fun for them.