Generally, it is recommended that men wear no more than two rings - one on each hand. The ring worn on the left hand should typically be a wedding band or other.
There is no scientific evidence that sleeping in a bra has long-term health consequences or any impact on breast size, shape, or position on the chest.
If you need to run, jump, or make sharp turns (especially if you have some ankle instability from an old injury), you'll benefit from compression socks. Unlike.
I'm not sure there is a “typical” age; I think it all depends on the girl. Some are ready right when their period starts, and some wait until they really feel.