How to tell the difference between a Man o’ War and a By-The-Wind-Sailor?

I saw something that was one of these on an east coast Florida beach today.

We had strong winds blowing a ton of sargassum onto shore yesterday so I figured I would see some jellies and stuff today.

It was in the sand and had one tentacle-like thing or maybe multiple tentacles clumped in a line that was maybe a foot long or more. Looked inflated and blue/purple/pink.

I was surfing so no phone to take a pic but is there a proper procedure to follow when you spot one? There were tons of tourist kids and dogs running around. I thought about putting some sticks around it at least. No lifeguard today.

Also didn’t realize these other creatures also got a cool ship name, haha I love it.