A character web for a novel can include many different components. The most common web consists of a single character's name in the middle of a page, surrounded by topics such as physical description, character traits, significant quotes, and important actions.
If you were going to do a character web for Lennie, for example, you would write Lennie's name in the center of the page and then draw a box around it. At the top of the page, you might write "Physical Description" and then include something like "strong and muscular; larger than the other men." Then draw a line from Lennie's name to that box. You could then add another box at the top of the same page with "Character Traits" at the top and then write something like "mentally challenged; trusts George completely; loves to pet small, furry animals; gentle but doesn't realize his own strength." Then draw a line from this box to Lennie's name box. At the bottom of your page, you could add a box for "Significant Quote" and then add something meaningful that Lennie said, like “I got you to look after me, and you got me to look after you, and that’s why.” Continue working through the character analysis until you have met your instructor's guidelines. Other characters you might want to consider are George, Candy, Crooks, Carlson, Curley, and Curley's wife. I am linking an eNotes page on the characters in this novel below.
Some character webs actually show the relationships between and among characters. In this case, each character only has one box on the page, along with a brief description of that character. So the box for Lennie might say, "A mentally challenged man who doesn't realize his own strength and accidentally murders a woman because he loves to pet soft things." You might then create a box for Curley's wife and describe her this way: "a lonely woman who feels ignored by her husband and frequents the ranch hands' quarters in search of male attention." The goal is to then show the relationship between these two characters, so you might draw an arrow from Lennie to Curley's wife and write, "intrigued by and accidentally kills" on top of that line. Of course, both Lennie and Curley's wife have various other relationships with other characters in the novel, so you'll need to explain how the characters relate to each other through your graphic representations.
I hope all of this helps you as you analyze various characters in this great piece of literature. Good luck!