Well Miss Camille, I don't know any more along the same meaning as "All hat and no cattle" but here are some other folksy sayings from Texas and beyond.
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The engine's runnin' but ain't nobody driving. (Not overly-intelligent)
As welcome as a skunk at a lawn party. (self-explanatory)
Tighter than bark on a tree. (Not very generous)
We've howdy'd but we ain't shook yet. (We've made a brief acquaintance, but not been
formally introduced)
He thinks the sun come up just to hear him crow. (He has a pretty high opinion of himself)
She's got tongue enough for 10 rows of teeth. (That woman can talk)
It's so dry the trees are bribin' the dogs. (We really could use a little rain around here)
Just because a chicken has wings doesn't mean it can fly. (Appearances can be deceptive)
This ain't my first rodeo. (I've been around awhile)
He looks like the dog's been keepin' him under the porch. (Not the most handsome of men)
They ate supper before they said grace. (Living in sin)
Time to paint your butt and run with the antelope. (Stop arguing and do as you're told)
As full of wind as a corn-eating horse. (Rather prone to boasting)
You can put your boots in the oven, but that doesn't make them biscuits. (You can say whatever you want about something, but that doesn't change what it is.)
Timing has a lot to do with the outcome of a rain dance. (The results of an action may not always be becuase of the action.)
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That's just a few for now but you know a guy like me has a bunch of 'em...lol.[/b]