So, the first thing you want to think about, and the most important, is the price. I suggest getting a price range that is not that wide, but not that small either. So just the perfect size for you. Make it something comfortable. Just for the sake of this tutorial, I will choose a price range between $150 and $350. I would suggest not looking at the websites for major big-box stores like Best Buy, Walmart, etc. because they sell for prices that are usually above retail price in order for them to make a profit.
The second thing that you will have to think about is the size of the monitor.. This is probably one of the most important things about a new monitor, because you don't want something to be too big, nor too small. Another thing to think about when deciding the size of your monitor is the space around your desk, or where your monitor will be. If you have an overhang, then I suggest measuring the height from your desk to the overhang and see if you will have enough room. Most monitors will fit, but there are some that have fairly tall stands.
The third thing that you must think about is what you will be using the monitor for. If you are just getting a monitor for everyday web surfing/schoolwork then you really don't need to go into much detail about the specs of the monitor and can settle for a very regular, everyday monitor. If you are going to be gaming, then I would care about the specs of the monitor you choose on getting.
If you are going to be purchasing a monitor for gaming, then I would suggest thinking about these two things: refresh rate, and response time. These are very important when it comes to games like Battlefield, because if you turn around a corner and see someone, chances are they've already seen you and you don't have a higher chance on killing them than they do, unless they have the same refresh rate and response time as you. The normal response time for a monitor is 5ms and is very common. There are monitors that can get you down to even 1ms response time, and it is also fairly common for gaming monitors to be from 3-2ms (millisecond). The most common refresh rate for monitors is around 60Hz (hertz). A lot of people that buy gaming monitors have about a 120Hz refresh rate, but 60Hz is still just fine if you can't get a good monitor for a good price with higher refresh rate. Some monitors even go up to 144Hz!
One more thing about choosing a monitor and the specs of it is the max resolution of it. If you are going with a 24 inch monitor, I suggest not getting it with a resolution of 1400x900 (900p). It just wouldn't look right. I suggest 1920x1080 (1080p) at least. There are some monitors that are 2560x1440 (1440p), but those are not very common. I would say that 1080p monitors are the most common.
Make sure to look at reviews on the monitor and research the company to see if the monitor you are thinking about buying is good!
OPTIONAL: The next thing you want to look for in a monitor is style. I don't want to have a monitor with just a plain old stand that my grandma has- no! I want something that my friends (if I have any will be jealous of when they see. If you are looking for style, and good specs on a monitor, then I suggest the Acer GD235HZ. This is probably one of the most attractive monitors I have ever seen in my entire life and I wish that other monitor companies would look at this and make their own really attractive monitors. The Acer GD235HZ has a very attractive transformer-like stand with orange accents and gives me goosebumps every time I look at it.
Now with all of these in mind, it should make choosing a monitor a bit less of a hassle.
With me using these tips, I actually chose a monitor myself, and seeing as I will use a monitor mainly for gaming, I came to the conclusion that it was going to be good. So I chose the BenQ XL2420TE. This is no ordinary monitor. It has a 24 inch 1080p display, 144Hz refresh rate, and a 1ms response time. BenQ is the MLG sponsored brand of monitors, so you know that they can be trusted. Here is a link to the monitor that is in the picture below:
I really hope that this tutorial helped out anyone that reads it, and good luck on purchasing a new monitor.