I did the same thing last week...deep cut on index finger. No first aid kit available but a piece of paper towel and rigging tape put enough pressure on to stop the bleeding and prevent a mess. I removed it about six hours later when I got home after working on the boat for the rest of the day. Better than a band aid.]
I have used rigging tape to make a bandaid in the past - a little paper towel and some antibiotic ointment and it will not fall off when soaking wet.![]()