i would wrap some paper around it then put some tape over it to hold it. only tape the paper, dont let the tape touch the stem. also dont do it too tight but not too loose either. if it's having trouble staying supported you can use a piece of wire or twist tie to hold it up in place with another branch. you could also put a steak in the ground and a twist tie around the branch to keep it held up.
if the leaves on that branch get all droopy and look like it's dying, then you may just want to cut it off.
i've had some pretty bad breaks with branches but been amazed at how resilient plants can be. good luck!