I've been lurking, but I had to sign up to let you know that I understand completely! I love shopping and clothes, but I get easily overwhelmed. Add to that the fact that I usually need petite sizes because I'm short and also the town I live in is so small, all we have is JCPenney and Walmart.
I've spent the last couple of years building a working wardrobe and I'm happy with the progress I've made, but it did take some time and a lot of thinking and planning. My advice is to first write out a list of what you currently have. I did this in an Excel spreadsheet, but you can do it anywhere. Break it down into categories: dresses, pants, tops, sweaters, etc. You can also use this time to remove any items from your wardrobe that don't fit or are stained or you don't really like and get rid of them. Don't second guess. If it doesn't make you happy, out it goes! Then go through your list and highlight or otherwise mark anything that needs to be replaced soon. For example, I really need new white camis to replace the old ones I have, so on my spreadsheet those are marked in red. I can see at a glance what items I need to find replacements for and I can build a shopping list from those. You can also use the list to then look for holes in your wardrobe. Maybe you have two items that would look great together, but you need one other thing to complete the outfit. Add those to your shopping list.
I agree with Sharon about colors. Figure out what colors flatter you best or what you like. The biggest thing that helped me create a cohesive wardrobe was to build it based on a core color group. I used to just shop and buy random things and think, "Oh, I don't have anything orange in my wardrobe, so I'll buy this orange top." But the problem was, the orange didn't go with anything else in my wardrobe because it was so random and it didn't flatter me. So I decided to focus on a few certain colors and build a wardrobe based on them. I find black too harsh on my skin tone, so my neutrals are browns, grays, and whites/creams. My colors are pinks and purples, with accents of yellow. These are my favorite colors and the ones I feel best in, so I focused my shopping on those. It can sound kind of boring, but I allow for a wide range of these shades, so my wardrobe includes anything from pale pink to coral and even the occasional red, and pale lavender to deep plum. I have pale yellows and bright yellows also.
This doesn't mean that I never buy anything in another color. I have a few navy items, and even a couple of black items (a dress and a cardigan), and the random outlier such as a mint green cardigan or a blue skirt. But I know that my core wardrobe can be mixed and matched because the colors I choose work together and are ones that make me happy. Whenever I go shopping, I know what colors I own and can determine if a new addition will work with everything else. If it doesn't, I put it back and find something that will. I have a great outlet mall about an hour away and I love it because my little town doesn't have any of the stores I like, but the outlet mall does. But still, I do the majority of my shopping online. I like having the items neatly laid out on the screen in front of me instead of crammed into racks. It makes me feel less overwhelmed and I can easily pick out items I like.
Mary also mentioned Pinterest and I have to agree! I LOVE Pinterest. I read various style blogs and I always pin outfits and items that catch my eye. It really helps to get a good look at what styles and colors attract you so you can figure out what to build your wardrobe around. I always knew I had a romantic fashion sense and my Pinterest clearly reflects that with all the ruffles and pretty dresses I pin, LOL! I also pin specific items from online stores that I like and sometimes I'll go back and actually buy the items I've pinned. I consider it my "thinking it over" board, LOL. I pin the item and then if I still love it the next day, I know it's a good addition to my wardrobe.
I hope that helps! Good luck!!
