Most animals (myself included) are basically a pear shape or bean shape which can also be thought of as a couple ovals mashed together. In fact you can do worse than to think of the entire body human or feline as a whole bunch of ovals mashed together.
Start like this
A couple more ovals form the neck and the head. But not the tail? Wrong, the tail is wrapped around an invisible egg shape. See it now?
If ovals stop working for you use straight lines where you need them. It's all about you and the look you're trying to achieve. Sometimes it's the juxtaposition of curved and straight lines that creates tension or movement in a drawing.This is as finished as I'll usually take the sketch before finding a model or photograph to work from because I know the details won't be right if I keep going, but the general mass shapes work.
It is fun to keep going and see how close to accurate you can get just from memory.
My human model was uncomfortable with me taking photographs of her which is certainly her prerogative, but unfortunately it meant no photos of the cat either. I've had to make up a lot of this drawing later and use photos of other people and animals.
That's OK, we have a beautiful jaguar at the Phoenix zoo. I have a membership which lets me get in early. Sometimes I've been able to sit quietly with this guy for an hour before the crowds come. He'll come right up as close to me as possible, look me right in the eye and talk to me. I don't speak jaguar, but I suspect he's telling me I look delicious.I've taken lots of photos, but none will be just what I want in any given drawing so I don't worry about it, I just let it guide me as I draw some kind of big cat.
This is the photo I used most for this image. Notice none of it is quite the same as it looks in the drawing, you don't need it to be.
Don't copy a photo of a cat and try to force that into your composition, it won't work.
Draw the cat the size shape and posture that you want, then find photos and start correcting your mistakes within the frame of your sketch. Make your reference conform to your idea, not the other way around.