#1 net the fish
#2 hold her in your hand, use a finger to open her mouth.
#3 I place my finger slightly in her mouth so she cant shut it or the fry can be damaged.
#4 swish her back and forth with the mouth submerged and open and the fry will smim out.
I usually do this in the net and then transfer the babys into a fry keeper in a 10 gallon dedicated to fry with the same water or similar.
Make sure your hands are wet and try to avoid touching her eyes.
Good luck, it is fun watching them grow and color up.