What to wear under motorcycle leather suit?

For cold weather:

If you are wearing a motorcycle leather suit, you won’t need much of extra insulation as leather is an entirely windproof material and will keep the cold air out and you will stay warm. A simple insulation shirt will work just fine. Thermal socks for feet and thermal gloves for hands and you will ride smoothly through the heavy freezing air.

Summers:

Summer can be exceedingly annoying for a rider wearing the motorcycle leather suit. The sweat and the heat make it hard to keep yourself maintained and fresh. Your socks, the shirt you are going to wear under, underwear and the socks must be made of moisture-wicking material. Moisture-wicking clothes take the sweat and moisture away from your body and are necessary if you want to stay cool during your ride.