Buying wine can be a scary experience for many people. There are so many selections, so many different wines to choice from. The wine displays are like advertisements. They have so many great words to say about the wine, they provide descriptions of the wine and many times a point value is displayed. Than you add the salesman who will attempt to steer you in the right direction. But I have found from working in retail stores and being a customer myself, there are some basics that you need to understand.
What type of wine are you looking for and for what reason ?
How much do you want to spend ?
What are your likes and dislikes ?
The Label
What Type and Why This is very important. You may be coming into a store just to find a bottle of wine that you can enjoy with that special someone that evening just to relax and enjoy each other. Or you could be looking for a wine to serve with dinner with friends. Still you could be selecting a wine to impress a business associate. As you can see, there are many reasons why someone wants to buy a bottle of wine. Once you know which of these is important to you, you should be able to work with a wine salesman to help you. If not, take your time, browse 
the aisles, look at all the displays, read all the descriptions about the wine. While some of the descriptions may sound so exciting, some may seem foreign to you. They may talk about the wine having an apricot nose, a jammy finish, currant overtones. Dont worry about that in the beginning. Then there is the Point rating system. There are three major wine organizations that rate wines and give a point value to them. You will always find those wines that have a 90 or above rating. 
That is suppose to indicate the quality of the wine. Two things to keep in mind here. That does not mean that you are going to like that wine! and secondly, many of those points are advertising related and like any other marketing industry there are some gives/takes on how a review is done
The Cost This is an important consideration. If you are basically new to wine, I would suggest not spending a lot of money on a bottle of wine. There are so many very good wines that you can purchase in the $8 to $12 range. 
So many customers have asked me over the years, Is a $100 bottle of wine ten times better than a $10 bottle? My answer is generally No, but it depends. For many people new to wine that $100 bottle is not going to be to their liking, mainly due to some of the complexity of that wine. While experienced wine drinkers will say yes. It really depends on your level of wine experience and appreciation. For the person first buying wines, it is a good idea to purchase 4 or 5 wines of different grapes styles (Merlot, Cabernet Sauvignon, Chardonnay, Rose, etc) all about the same price range. Take the home and try them out to see which ones you really like. Then the next time you go shopping, try another vineyard of the grape style that you liked. Then after several months, purchase those same grape styles, but at slightly higher price. Do this slowly and see if you can notice any differences between the same type of wine, but at different price points.
Likes and Dislikes This is very subjective. Each person has their own likes and dislikes about anything. The same goes for wine. Some people dislike any wine that is dry and will drink only sweet wines. Then you have some people that say they dont like wine at all, or they done like red wine or white wine. I’ve always believed there is a wine for everyone, you just have to find it. In the beginning, I suggest sticking with your likes, but I also encourage people to branch out after a while. I have found that people who like sweet wines, the more they try different wines, they start to gravitate to drier wines. And for those folks that say, I dont like wine at all The white or red blends are perfect wines for them. They are generally soft and so easy to drink. Any salesman should be able to so you the many blends that are on the market today.
The Label This can be a two edged sword. Wine labels contain detailed information about the wine, almost to the point where you can anticipate what the wine will taste like. 
But on the other hand, because of smart marketing ideas, there will be labels that will just catch your eye. So many people have purchased wines because they like the label without knowing anything about the wine or type!
To buy wines on a regular basis, it is important to get to know your salesman. You may want to visit many different wine retail shops to look over their inventory, their displays and to talk with some of their salesman. Is the person pushy? Are they just trying to sell you any wine? Or will they spend time with you listening
to what you like and dont like, etc When you find a salesman that you can trust, then you will have made your wine buying that much easier.
Over time, you will develop better skills in selecting the wines that you want. Part of this process is also finding a wine salesman that you trust and know that they are working with you to find the right wine at the right price just for you.
In the end, purchasing wine should be a fun event, 
something that you can look forward to do and find excitement about all the different wines.