Thanks, clarousel!
Good idea to lure your budgie to the scale with a treat! Try to make it as easy as possible for the behaviour to happen. What will your budgie step onto? My Pionus, Kobe, would not step on a metal object like that, but he will walk on a magazine. So I put a magazine on the scale before I switch it on. Or you could try a cloth, or newspaper. Some scales have a perch that you screw on, but failing that you could aways put a table top perch on top of the scale (just make sure it is secure), or even a block of wood. Leave it in view so that she gets used to it. You could even put toys on it to tempt her to play on it.
Next shape the behaviour. It is too big a step to expect her to get onto a strange new perch, so break the behaviour down into tiny, manageable approximations/steps. Make it easy for her to succeed. If you are going to carry her over, have her step up on your hand and turn towards the scale. Reinforce her relaxed body language with a treat. Take a small step towards the scale. Treat! Take another small step towards the scale. Again reinforce her relaxed body language with a treat. You might want to leave it there for that session. Next session see if you can get closer still all in teeny tiny steps.
If you are going to give her space to walk to the scale herself, again, break it down into tiny approximations, and reinforce those approximations along the way with a treat. Always end on a successful note. If she fails a step, then go back a step or two and make the approximations smaller. Make the training sessions very short - a few seconds here, a minute there throughout the day. That way you can get loads of repetition and repetition = learning.
