Keep the class in their groups and give each group three or so proverbs to try and work out. The pen is mightier than the sword. The early bird gets the worm. It takes one to know one. One in the hand is worth two in the bush.
Every cloud has a silver lining etc.
After around fifteen minutes, again get feed back. Some will be right on the nail while others may surprise you. Give the meaning where groups have not worked it out. Finally keep them in their groups and ask them to think of three proverbs in Thai, which they will explain to the class. Tell them you want three things 1.