The answers are below but see if you can guess the saying behind each piece of conventional wisdom: 

1. Fix something right away or it will get worse.
2. An overabundance of culinary help is detrimental to the pot's contents.
3. Just because something is shiny, doesn't mean it's a precious metal.
4. That which pleases the eye doesn't go beyond the epidermis.
5. The capital of Italy was constructed over a long period of time.
6. There comes a time when your canine friend is through matriculating.
7. If you're going to give advice to others, be sure you follow it yourself.
8. Just because you aren't punctual doesn't mean you should quit.
9. If you never try to do anything, you'll never get anything done.
10. It doesn't take long for a person without good sense to be separated from his financial assets!

Answers:

1. A stitch in time saves nine.
2. Too many cooks spoil the broth.
3. All that glitters is not gold.
4. Beauty is only skin deep.
5. Rome wasn't built in a day.
6. You can't teach an old dog new tricks.
7. Practice what you preach.
8. Better late than never.
9. Nothing ventured, nothing gained.
10. A fool and his money are soon parted.