Whose is possessive. “Whose toys are those?”
Who’s is a contraction of who is. “Who’s going with me?”
Just remember: Who’s going to find out whose car that is?

Were is a verb. “They were going on vacation.”
We’re is a contraction of we are. “We’re going to the restaurant.”
Just remember: We’re touring where they were quarrying stone.

Where involves location. “Where is the car show?”
Wear involves clothing. “You should wear the blue shirt today.”
Ware involves merchandise. “The potter is selling his wares.”
Just remember: Where is the painter that wears tie-dye selling his wares.