Compliment what does work
Rather than only harping on what looks terrible (the brown fleece pullover you can't stand or the ill-fitting jeans he insists on wearing) try to help him make note of what looks good on him and why. Start with color – ifthe fit is terrible does the baby blue T-shirt bring out his eyes? Tell him. Alternatively, if he owns a great sweater in a less-than-stylish hue, let him know you like the fit but the shade isn't for him. Hopefully, your strategic comments will help guide his next purchases.
Build on his preferences
Like complementing what works, making suggestions based on colors or styles he already seems partial to can tip the fashion hand in your favor. If he likes green but everything green he owns is, well, outdated (by a decade), then suggest green items that you feel would look good on him. That way, the suggestions you make aren't coming completely out of left field and you're giving him something he can work with.
Go shopping with him
If your helpful hints don't work, you can always try going shopping with your guy. That way you can actually point out the items you have in mind for him, hoping he'll agree to try them on. Often, once a guy sees how much better he looks in something that suits his size and frame (and doesn't have holes or stains on it); he'll become much more conscious about what he wears.
Buy clothes for him
The quickest option to improving his wardrobe is to take matters into your hands and purchase a whole new outfit for him. This isn't ideal since the cost is coming out of your own wallet, but if only do it once (and you can afford it), the results can be worth the time and money. Some guys just don't understand what looks good on them so they need hands-on help. Happy shopping!
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