Well, as far as my experiences go, men's clothing are not made to 'fit' or 'work right' on female-shaped bodies.
Men don't have much in the way of hips and butt when compared to women, though there may be exceptions, rare as they may be.
You might have to settle for buying female clothing that looks more male. Hard to come by, yes, but it's possible.
That, or you'll have to focus more on illusions and changing your body to fit the clothes - if you're good with a sewing machine, then tailor the clothes yourself.
There are tricks that you can use to lessen the looks of hips and butt.
One thing that I find particularly effective is to wear button-down shirts over a t-shirt, make sure they're long enough and this will make your hips and thighs and butt mask a bit.
I also find that focusing attention on your upper half also helps; wear eye-catching shirts, or even hats, and people are less likely to notice your hips and butt; stay away from decorative belts and buckles and the like.
I don't have time to write everything else that I was thinking, but vertical strips also help you make longer, but pin-striped pants look funny unless in the right setting, so keep it in your shirt.
There's also other things you can do, just look up fashion tips and such.
Good luck!
