The long lycra suit is one solution but over 55 years diving (both wet and dry) in various suits here's another idea.......
When I was a scuba instructor 1978 - 1990 here in Ohio students would do their certification dives at our local quarries, White Star Quarry and Portage Quarry (which is long closed.)
Our rental wet suits (plus personal) were usually a 2 piece 1/4" thickness, close to 7mm.
Most divers had a swimsuit on. Long sleeve rash guards were just becoming popular but getting legs in the pants (farmer john style) was more the struggle.
I thought somewhere I read California beach divers used what they affectionately called "slime". Basically it's a 1/2 bottle of any hair conditioner (biodegradable) and water in the hair conditioner bottle. Shake it up........
We'd squirt a shot in each leg and voila', your suit would slip on like butter
Some folks put a squirt down the arms also.
Later as one piece suits (especially in more progressive scuba stores who disliked having to deal with 2 piece suits as rentals) it was a lot easier technique getting folks into a thick wet suit versus plastic bags, etc. .
Lycra full body suits do help also these days but slime also makes your skin soft and smells great
Just one old time diver's idea!
David Haas