It is best to wear layers so if you are too hot you can take a layer off.
Layers are good, they trap heat, allow sweat to move through the layers of clothing. Moisture is wicked away inner layers to outer layers and then evaporates.
So try – wicking base layers, insulating middle layers and wind /waterproof outer layers.
We lose a lot of heat through our extremities so hats and gloves should be considered.
Vaseline to protect your lips from chapping.
Legs generate a lot of heat so one layer is fine unless below 10 degrees then you may want to consider two layers