How does Steinbeck portray women in Of Mice and Men?

The fact that the main female character in Of Mice and Men is referred to as either a “tart” or as “Curley’s wife” indicates that women in the 1930s setting in which the novel takes place are one of two things: sexual objects or men’s property.
The objective point of view of the novella’s narrator also means that we only know what the characters say, see, do, and hear. Curley’s wife's namelessness, then, is the result of no other character ever asking or hearing her name. This indicates the way women were viewed as extensions of the men with which they belonged.
Furthermore, she is described as a caricature of femininity with her sexualized body language, her fancier-than-necessary clothing, her “sausage” curled hair, and her heavily made-up face. The color red (fingernails, lips, shoes) reinforces her lustful representation. Alongside this description, George refers to her as “jail bait.” While readers never learn her exact age, it can be inferred that she is rather young. In light of this, her overtly sexual presentation suggests that the men see her as a temptress.
Despite George’s wariness of her, most men on the ranch enjoy ogling her while calling her derogatory names behind her back. While the men join in sexualizing her, they also disapprove of her behavior as a married woman. This reflects larger social attitudes of the time about gender roles.
In 1938, Steinbeck himself wrote a letter to the Broadway actress Claire Luce, who would assume the role of Curley’s wife on stage for the first time in the adaptation Steinbeck helped author. In this letter, Steinbeck explains his vision of Curley’s wife:

She learned to be hard to cover her fright. And automatically she became hardest when she was most frightened. She is a nice, kind girl, not a floozy. No man has ever considered her as anything except a girl to try to make. She has never talked to a man except in the sexual fencing conversation. She is not highly sexed particularly but knows instinctively that if she is to be noticed at all, it will be because some one finds her sexually desirable.
As to her actual sexual life—she has had none except with Curley and there has probably been no consummation there since Curley would not consider her gratification and would probably be suspicious if she had any. Consequently she is a little starved. She knows utterly nothing about sex except the mass misinformation girls tell one another. If anyone—a man or woman—ever gave her a break—treated her like a person—she would be a slave to that person. Her craving for contact is immense but she, with her background, is incapable of conceiving any contact without some sexual context. With all this—if you knew her, if you could ever break down a thousand little defenses she has built up, you would find a nice person, an honest person, and you would end up by loving her.

According to this excerpt, Steinbeck conceived Curley’s wife as an inexperienced, intimacy-craving person who believes the only way she can get attention from others is through manipulating their sexual desire for her. Overall, while men in the text view women as sexual objects or property, Steinbeck hoped to create a complex character with a stereotypical appearance—and he lets the reader interpret her motivations.
Besides Curley’s wife, the only other women mentioned are the girl in Weed, prostitutes in town, and Lennie’s aunt Clara. These mentions also reinforce attitudes toward women. George characterizes the girl in Weed as a manipulative liar (she claimed Lennie raped her when all he did was touch her dress, according to George). George remarks that he isn’t interested in settling down but might spend money on a “flop,” if he wasn’t trying to save up his and Lennie’s stake. Aunt Clara, meanwhile, is an old-maid type who cared for Lennie when he was a child.

One of the questions that lingers in Of Mice and Men, is whether or not Curley's wife was "asking for it". A phrase or question that is often asked to today's women when it comes to sexual assault: What were you wearing? Why were you by yourself? How much did you have to drink?
However, when it comes to Curley's wife, the question can make readers wonder whether or not she was actually "asking for it"- with the "it" being her death. When the reader takes a breath and realizes that no one would "ask" for the violent death that Curley's wife endure, the reader inadvertnly realizes the power of Steinbeck's words.
Through sexist comments and slurs, Steinbeck has turned a victim into one of the most hated characters in the novel. There is no clear cut theme of sexism in the play, not one character says "Oh, it's different because she's a women" and yet, this could still be seen as an accurate comment on today's society.
Steinbeck might not have given Curley's wife a name, but he did give her animalistic characteristics. Often referring to her as "a bitch" or at times "Lulu', the name of Slim's dog. However, when Candy's dog is shot, there is often a sadness or empathy that connects the readers to this moment. Could that be the same for the death of Curley's wife? The answer, for most, is yes. However, for some, and for the audience that read this in 1937 the question lingers: Was she "asking for it"?

There's only one female character in Of Mice and Men, and that's Curley's wife. The fact that we never find out her real name speaks volumes about how she's portrayed in the book. She's not exactly the most sympathetic of characters, it has to be said. She comes across as a rather shallow, superficial woman who cynically uses her overpowering sexuality to get what she wants. Threatening to have Crooks lynched also indicates that she's a racist to boot.
Yet Steinbeck is way too good of an author to write such a one-dimensional character. There's more to Curley's wife than just her brash, voluptuous exterior. For one thing, she's very lonely—not surprising when you consider that she's the only woman on the ranch. She also has ambitions in her life, with dreams to make it big in Hollywood. Someone once told her she had acting talent, which may or may not be true.
For all that, though, the abiding impression of Curley's wife is that she's trouble. But then again perhaps she needs to be, as it's the only way she can survive in such a male-dominated environment. She's had to develop a tough exterior to make her way in this world. Yet trouble comes to Curley's wife when Lennie kills her, just as trouble came to the poor young girl in Weed to whose dress Lennie took such a fancy.