But first she has to understand about Cuckolding and will have gone that far to either like it or not.
How to do it if she is the one wanting it. Usually it's the man who wants it. He gets excited thinking of his wife with another man and starts to encourage his wife in the direction of other men, he will hint about Cuckolding and get his wife's interest who in turn will read all about it on line. She will either be against it or want to embrace it. If she does find nice good lovers that of course she will like Cuckolding her husband.
But cuckolding is not something to do once or twice, in a women's case she will want it often it can take control of her and she will make her husband a total submissive she will control him and if she has any sense she will make him into a sissy cuckold, it will keep his mind and body occupied with silky thoughts and feelings. He will be much more placid and most men love the feel of silky satin lingerie touching most parts of their body, just as a women does.