I bought a pet scale so I can gauge my cat's weight loss progress but I can't seem to convince him to get on it himself and when I lift him into it he gets scared and squirms himself away real fast. Impossible to get his weight. What do?
Depending on the size and stability of your pet scale I would try throwing a few pieces of kibble or something he can't resist onto the scale to get him used to moving onto the scale. When he feels more comfortable with the machine you'll be able to weigh him easily. If the scale is rather small and unstable, you will not have much success as he will prefer to leave one or two feet on solid ground.
If he goes into a carrier without much fuss, you will be better weighing him in the carrier and subtracting the weight of the empty carrier.
Alternatively, if you can hold him comfortably, use a normal bathroom scale, weighing first both of you together and then subtracting your weight.
I am once again having problems trying to weigh Mogi. She got used to going onto the scale voluntarily but something spooked her so we're back to square one! CATS!!
My daughter was a wrestler so we got a digital scale that is reasonably accurate to tenths of pound. Don't think they are too expensive at this point. So to way a cat we do human + cat - human. Easy, and it seems reasonably accurate compared to the vet. If you can't pickup and hold your cat for a little bit, you'll need another method such as what gilmargl
I went a different approach. My seven year old cat, Reggie, had lost a lot of weight due to some medical issues, and in order to verify and track his recovery (and he is recovering nicely, thankfully!) I got a baby scale.
As to how I get him to use it - I have it on the floor against a wall in the room I feed him. For one meal every couple of days, I kneel in front of the scale (so he has to approach from the sides) and just use his food bowl to maneuver him onto the scale - so if he approaches from the left, his food bowl goes to the right of the scale, and so forth.
It's pretty quick and easy, and he's totally happy to stand on the small plastic "cat bed" and eat his food.