Much simpler: fit it properly.
Whatever you do, don't ride with it loose. You'd damage your hub.
Remove the crank. If it works really loose, you might be able to do
this by hand, or it can be achieved with a suitable combination of
blocks of wood and a mallet.
BUT, as with every job, the best way to do it is with the proper toll,
which is handily designed for the job. A crank remover tool is an
essential part of my tool kit.
Remove the crank. Clean the mating surfaces on the inside of the crank,
and the tapers of the hub. Put the crank on neatly, then tap it into
place with a rubber or wooden mallet (or a big block of wood and a
hammer). A couple of sharp taps will do more good than lots of tappity
taps.
The idea isn't to force it on really hard, but to make sure it is
properly seated.
Now tighten the nut or bolt (varies depending on what type of hub you
have) with the 14 mm socket.
Rid for a few hundred metres, then get off and tighten it again. Check
it again a few hundred metres later, and then it should be OK.
Every ride, just check it hasn't started to come loose - especially if
you ride hard, do big drops or fall off a lot.
--
Mikefule - The first cuckoo of unicycling
Sumer is icomen in, loud sing Mikefule!
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