Don’t Shop Aimlessly; Have a Plan
If I could only give three pieces of advice to a budding clothing enthusiast, they would be: find a good alterations tailor; learn how clothes should fit; and set a plan for your purchases.
I can’t stress the last point enough. Having a plan means that you’ll be more likely to build a wardrobe of versatile clothes that easily combine into outfits, rather than just a collection of various things that happen to have caught your eye. To set a plan, begin by determining your annual clothing budget. Once you’ve figured out what you can afford, allocate between half and to three-quarters of your budget to shoes, suits, sport coats, and outerwear. These tend to have the biggest ticket prices, but also the highest pay offs. You can easily look great with an excellent sport coat or jacket, even if you’re just wearing it with a mediocre button-up shirt and cheap pair of chinos.
The rest of your budget should be spread between trousers and shirts, and maybe a small amount allocated to sweaters and accessories. 
Now go through your wardrobe and figure out what holes need to be filled and what basics need to be replaced. As much as you can, try to cut your wish list in half and double the budget allocated for each item. You’ll always be happier with a small wardrobe filled with higher quality pieces than you will with a large one filled with half-neglected cheap items.
It’s too much to expect that each person out there has the same clothing needs as I do, but if I had to make a recommendation, I would say you should try to acquire two or three pairs of shoes a year, maybe the same in outerwear, and perhaps one or two sport coats or suits per season, depending on your lifestyle. This, in addition to what you’ll purchase in shirts and trousers, should put you on track to building a respectable wardrobe in about three to five years’ time. 
I update my list constantly, and frequently mull over what I should add or drop. My list helps me figure out what I want my wardrobe to look like in the long-run, and whether I have too many navy sweaters and not enough grays, or too many fall jackets and not enough for spring. Once something has been on my list for a while, I try keep the item in mind while shopping. And by sticking to my list, I’m able to avoid compulsive purchases. This is especially useful during sale seasons, when one might think that a padded tweed jacket with a faint windowpane check is more worth purchasing than it is. If it hasn’t been on my list for a while, it’s probably not something I’ve thought about long enough. 

Don’t Shop Aimlessly; Have a Plan

If I could only give three pieces of advice to a budding clothing enthusiast, they would be: find a good alterations tailor; learn how clothes should fit; and set a plan for your purchases.

I can’t stress the last point enough. Having a plan means that you’ll be more likely to build a wardrobe of versatile clothes that easily combine into outfits, rather than just a collection of various things that happen to have caught your eye. To set a plan, begin by determining your annual clothing budget. Once you’ve figured out what you can afford, allocate between half and to three-quarters of your budget to shoes, suits, sport coats, and outerwear. These tend to have the biggest ticket prices, but also the highest pay offs. You can easily look great with an excellent sport coat or jacket, even if you’re just wearing it with a mediocre button-up shirt and cheap pair of chinos.

The rest of your budget should be spread between trousers and shirts, and maybe a small amount allocated to sweaters and accessories.

Now go through your wardrobe and figure out what holes need to be filled and what basics need to be replaced. As much as you can, try to cut your wish list in half and double the budget allocated for each item. You’ll always be happier with a small wardrobe filled with higher quality pieces than you will with a large one filled with half-neglected cheap items.

It’s too much to expect that each person out there has the same clothing needs as I do, but if I had to make a recommendation, I would say you should try to acquire two or three pairs of shoes a year, maybe the same in outerwear, and perhaps one or two sport coats or suits per season, depending on your lifestyle. This, in addition to what you’ll purchase in shirts and trousers, should put you on track to building a respectable wardrobe in about three to five years’ time.

I update my list constantly, and frequently mull over what I should add or drop. My list helps me figure out what I want my wardrobe to look like in the long-run, and whether I have too many navy sweaters and not enough grays, or too many fall jackets and not enough for spring. Once something has been on my list for a while, I try keep the item in mind while shopping. And by sticking to my list, I’m able to avoid compulsive purchases. This is especially useful during sale seasons, when one might think that a padded tweed jacket with a faint windowpane check is more worth purchasing than it is. If it hasn’t been on my list for a while, it’s probably not something I’ve thought about long enough.