Salt water is great for skin healing and drawing out any impurities or minor infection.
Vaseline is also good for putting onto the skin afterwards, it helps keep the scab soft and avoids a cratered look to the scar site.
I cut the bridge of my nose a couple of hours before my IM swim start. Had one of those see through plasters on but it was still bleeding. Removed the plaster and got on with my sea swim.
About an hour later, it was clean, no longer bleeding and had scabbed up nicely by the time l got to the finish line.
You can also get silicon plasters for scar improvement, they work pretty well.