Mrs Andelin in her book "Fascinating Womanhood" devotes a chapter to the feminine appearance. According to her, a really feminine woman will give "...careful attention to her appearance." (F.W., Bantam Books 1992, p. 248.). She will try to look pretty at all times, and won't neglect her figure, hair, face or clothes. However, it's wrong to focus entirely on one's looks and spend hours in front of the mirror, forgetting about domestic duties.
An ideal woman will spend her day running the household, but she will do it while looking her best. Mrs Andelin points to the famous Proverbs 31 lady who despite all the things which she does at home, finds time to make beautiful clothes for herself: "She makes herself coverings of tapestry, her clothing is is silk and purple."
Unfortunately, nowadays women aren't taught any more how to look and behave in a feminine manner, as the society ideal for women is to copy men. Things started changing recently as we see the revival of interest in femininity and traditional female occupations, and dresses and skirts made a comeback. Helen Andelin gives tips on how to acquire the feminine appearance.
The key to a feminine appearance is accentuating the differences between yourself and men. "Wear only those materials and styles which are least suggestive of men's and which make the greates contrast to their apparel." (F.W., pp.248-249).
Mrs Andelin suggests following several rules:
First, you are to avoid fabrics typically used by men, such as heavy denim. Instead, you can wear soft fabrics, woolens, silk, crispy cottons, lace etc.
Second, chosing the right colours is important. Drab colours such as khaki are unfeminine, instead switch to pastels, clear colours and the like. Black is OK, though.
Third, avoid loud prints and any fabric design which lacks good taste (I once saw a lady draped in black fabric with white skulls and bones; unless you are going to a pirate-themed party you can better avoid it!:)
Fourth, the style is also important. Masculine styles are: pants, mannish jackets and coats and the like. Extreme feminine styles are full skirts, ruffles, puffed sleeves etc. Even a plain dress/skirt is more feminine than a pair of pants.
Fifth, Helen discusses wearing pants. Pants aren't the most feminine of garments, but women seem to be quite attached to them nowadays so Mrs Andelin suggests at least wearing a more feminine model and combining it with a feminine top.
Sixth, don't forget about trims, i.e. lace, ribbons, embroidery and things like that.
Seventh, the same goes for accessories. Anything masculine such as briefcases should be avoided, instead wear feminine scarfs and jewelry.
Eighth, don't forget about grooming and make-up. It's important to look clean, have clean hair and laundered clothes. In Helen's times it wasn't a problem, but we have to deal with it, so I'll add: please avoid covering yourself with tattoos. They are hideous and men will perceive you as easy. Don't believe me? Read what men actually think, instead of what MSM told you they do: The slut sell.
Last but not least, let's not forget about modesty. I'd like to quote Mrs Andelin in full: "...decent men don't respect women who expose too much of their bodies in public. Not only should the body be modestly covered, but the underwear. Men dislike visible slips, bra straps or exposed underwear. Higher types of civilisation have traditionally been modest. It seems to go with intelligence and refinement." (emphasis mine).
Looking feminine increases a woman's self-esteem and brings a favourable response in a man. Nice clothes don't have to be expensive, either. For instance, I bought this dress in a second-hand store. It cost me all of 10 euro:
Butterick pattern page for the ideas.
And, as Mrs Andelin points out, your husband will surely appreciate it!