You see, the stock market, which is much like the one in real life, is something that neopians can turn to, to make some extra neopoints. Once you get the hang of the stock market, you can be RICH, to make it plain and quite easy to understand. This is basically a way to gamble, but in a way, but it's not really what I would call "gambling". Here is the way the game works, everyone: You buy stocks and then sell them when they go higher than what you originally gave for them. Here is a little screenie I took that will help you understand how stocks work.
In this screenie, you will notice that the parts of a stock are numbered. I will explain them all.
#1 - This is the logo.
#2 - This is the ticker. The ticker is very important when it comes to buying shares, because you need this to buy them.
#3 - This is the full name of the company.
#4 - This is the volume...
don't worry about it, because it does not affect the stock market in way.
#5 - This is the price of the share as of midnight NST of today.
#6 - This is the price of the share now AFTER the change. Shares' prices can change throughout the day. Of course, your shares' prices may not change for days, so don't watch your stocks 24/7; A watched pot never boils.
#7 - This is the percentage of the change. This is
very important, but unless you're a math genius, don't worry about it [much]. The only time when you should worry about it, would be as if it reaches to 100%, 200%, etc etc etc.
This brings me to my next screenie to explain this further.

This [old] screenie was taken from my portfolio.
#1 - Number 1 shows how much [np] you have spent all together, for the shares you have.
#2 - Number 2 shows how much they're worth as of the current change.
So this is why I say that you really don't have to worry about the change. Just remember this:
Green is good.
Red is bad.
Or, here is another way of putting it.
If your change percentage is
Green, then it means that the value [which means how much it is worth] of your shares has gone up.
The higher your percentage, the more value your shares have.
If your change percentage is
red, it means that the value of your shares have gone down. The lower your percentage, the less value your shares have.
My friend, this one is simple.
#1 - Find the stock you wish to buy. Please be sure that they are going for about 15 or 16np a share. And remember that if you don't buy 1,000 shares, in my view, the stock market isn't worth it. Be sure that you have 15k or 16k THAT YOU DON'T NEED to be able to invest.

#2 - Click on the TICKER (For example, in the screenie above, the three capitalized letters, "TPP".)
#3 - You will come to a page that has a table that looks like this.

Click on the name of the company. (For example, in the screenie above, the name of the company is, "The Presidential Palace.")
#4 - THEN You'll come to a little table that looks like this.

Please bear in mind that you can only buy a maximum of 1000 shares a day. This requires a little bit of math. Take how much the shares are worth and multiply it by how many shares you want of it.
For example, in the screenies above, TPP is worth 15np a share. If you would like 1000 shares, you take 15 x 1000. That will give you 15,000np that you owe for how many stocks you want.
#5 - Then click 'Buy Shares'.
To sell your stocks, follow these simple steps.
#1b - You go to your portfolio (Be sure to have 20np on hand for fees).
#2b - Then you click on the little arrow by your company's LOGO (as shown in the screenie).
Now to sell stocks.

#3b - This will bring in a little drop down window under the shares from your company.
#4b - Type in how many shares
you want to sell.
There ya go! That is how you buy & sell stocks!
If you see a stock that is available for 15, but the percentage is in the red, go on ahead and buy it! Don't be afraid. The Stock Market is a test of patience.
How do you see your portfolio [to check up on your stocks]?
A: Right
here.
What are the best stocks to invest in?
A: *sighs* This is a two parter answer.
If you are meaning any stock in-particular, like TPP, or FAER... then there is none, because stocks are completely random.
However, you should invest in the stocks that are going for 15, or 16np a share. Because that way, if they skyrocket, then you'll have a hefty profit. =]
Oh no! I think my stocks went bankrupt!
Don't panic, because chances are they aren't bankrupt. The first thing to do, is check and see what they are going for. If they are going for 6np a share (or higher), don't worry! They're just on the borderline of going bankrupt, but chances are they won't. If they are going for less than 6, then I apologize, but you have gone bankrupt. But not to worry, my friend; The last bankrupt known was in 2004.
How high should I let the shares go before I sell them?
I usually wait, along with other neopians, for them to go double for what you gave for them. Or, if you are the risky type, then I would go further.
For example. I would buy 1,000 shares for 15,000np. I would wait for the value to go to 30,000, or maybe even 45,000. For more in-depth info, go
here.
For more tips and secrets, please check out the 'quick tips' section in the left column under the links.