Hi,
Finer than frog hair.
Happy as a pig in (mud, or other yucky stuff)
Even a blind dog finds a bone some times
Three shakes of a lamb's tail
Grinning like a Cheshire cat
Grinning like a cat that just ate the canary
Sing like a canary
Darker than inside a well digger's (hip pocket)
Colder than a witch's (chest) in a stainless steel bra
Slower than molasses in January
Hotter than a $2 (pistol, or "working girl")
Last(s, ed, ing) as long as a June frost
Nervous as a ("working girl") in church (or cat on a hot tin roof)
Dumb as a box of rocks (or sack of hammers)
If (your) brains were dynamite, you couldn't blow your nose
Knee high to a grasshopper
Two years older than dirt
Ugly as a mud fence
Pretty as a picture
Lickety split
Step lively
The second Tuesday of next week
I was born on a (Tuesday, etc) but it wasn't last week
Rick C