If you have your directories set up appropriately (i.e., your lab directory is in your cs111 directory), you should be able to run
pairturnin labx partnerusername
where labx is the name of the lab you are submitting and partnerusername is your partner's username on the lab machines–the user whose account you are not working on.
Run this command when you want to “checkpoint” your code such that either team can access it.
For example, you could run
pairturnin lab6 sprenkle
if you are working on lab6 and your partner's username is sprenkle.
If you and your partner wrote the code on his/her account, you'll probably want to get a copy of the code on your account. You can do so by executing
indiv_startup labx partnerusername
where labx is the name of the lab you are working on and partnerusername is your partner's username on the lab machines.
For example
indiv_startup lab6 sprenkle
if lab6 is the name of the lab you are working on and sprenkle is your partner's username on the lab machines.