To create the hand bones, select the arm terminator (nub) bone (the small one at the end of the chain), and from the bone tools menu (go to the Character menu, and open the Bone Tools floater), turn on Connect Bones... a dashed line will appear... select the root bone for one of the fingers. A bone will be created in between them, and will be automatically set as the parent for the finger root bone. Check it's orientation. If you need to adjust it (very likely), unlink the finger root bone before doing so, rotate the hand bone, and relink. Here's what the connection bone (hand bone) looks like once you've completed the operation...
Fig 7. Hand bone.
Repeat for the other fingers.
Fig 8. Finished hands.
The legs are pretty straightforward. Create them in the left viewport, and again, make sure to move and rotate them into position. Also, remember to check for proper bone orientation. If you did create them in the left viewport, you should be ok. Here's what the finished legs look like...
Fig 9. Legs.
The feet should also be created in the left viewport. Create them just the way you see them, and afterwards move/rotate them. You can do this by moving the root of the foot chain to the leg's terminator position (align them in position pivot-pivot), and then align the foot's root bone orientation to the thigh or calf bone's (x,y, and z orientation, pivot-pivot). Here's a view of the finished feet.
Fig 10. Feet.