git stash push -m "message"
where "message" is your note for that stash.
In order to retrieve the stash you can use: git stash list. This will output a list like this, for example:
stash@{0}: On develop: perf-spike
stash@{1}: On develop: node v10
Then you simply use apply giving it the stash@{index}:
git stash apply stash@{1}