It sounds obvious, but have you written your name and contact details on your surface detection aids? The RNLI recommend that you do.
A lifeboat crew recently recovered a Delayed Surface Marker Buoy (DSMB) floating in the sea. They didn’t know whether they had retrieved a misplaced DSMB, or if they needed to commence a search for a potential lost diver.
As a minimum you should write your name on your DSMB, because it helps the skipper to know who is underneath the surface detection aid when you are sea diving.
The RNLI would prefer it if you also add your mobile number. That way if they find your DSMB, they can learn within minutes if you are missing and need help, or if they have recovered the delayed surface marker buoy you lost.
Just grab a permanent marker and neatly print your details onto the DSMB. Remember the name needs to be read from afar. When the lettering fades, just refresh the text accordingly.