Babies want to get out. They want room to fit in mother and they want to be able to move to a position so they can maneuver the birth canal with the least restrictions.
How can you help mom? Create space for your baby. Some possible ways to do this is to stretch using forward motions. Lean over a table or step and stretch one arm upward at a time. Place the knees and hands on the floor and stretch legs outward. In the yoga cat and cow positions arch the spine with the belly towards the floor.
What not to do? Do not sit all day. Do not be in a recliner chair. Do not sit in the car or bucket seats without extra back support.
Be kind to your baby. Create more space. Move, walk, swim, weed the garden in a squat (especially if baby is head down already.) And talk to baby. Let baby know you'd like baby to move to the easiest way for baby to come out. More on this later. Mom's help baby's come out.