Take one of these:
VOILA! Baby wipes!
If you are travelling or going out, stick them in one of those reusable containers that everyone has knocking around in the back of a cupboard somewhere.
First, rinse cloth in very, very dilute tea tree or lavender solution to wipe sticky faces and fingers etc, then fold and pop in a tightly sealed container. If baby has a sore bottom first soak cloth in a dilute chamomile solution first.
You now have your own box of free-ish baby wipes!