to teach stand command :
from down/sit position : Slide your hand under his belly like above until he stand up, give command 'stannndd....' (drag the command longer) you can put your hand under his belly near further end of his hint leg to block him moving forward or lying down before end the command. Praise after he 's in right position after few seconds.
from walking : if dog walking on your left parallel with you, use your left hand palm face down move along from his right eye to his left eye and along his belly until his hint left leg, give small tickle on his left tight to steady his stand and give command 'stannnnddd..'. praise after few seconds he 's in the right position.