I know the "How to make your own Minecraft server" topic has been done to DEATH by now, but this is a simplfied way to do it that I don't think many people know about. So lets get to it!
EDIT: This is also the way I'm hosting my Bukkit server that me and my friends have been working on till I get the steps of portforwarding down, or I have enough money to buy a server.

Step 1: Server Software:
This step is completely up to you. What you want to do is download your server software, it could be Bukkit, the minecraft server software from minecraft.net, or some other software I don't even know about! Just download it as you normally would, launch it, then stop the server once it has all the files in the folder. On the other hand, here's a more simple approach, make a LAN server. And yes, you can use this to let other people connect to your world with a client that I'm going to talk about in a second. Make a new world with the settings you want for it, Open it to LAN, and viola! A server!

Step 2: The Evolve Client:
This is the client I'm talking about. Evolve. This is a client for you and your friends to host parties, chat with people, and find other servers. The main thing that you'll use from this client in this tutorial is the VPN. It's like hamachi, but it's sorta in the form of an Xbox Live party. You can use a mic or headset and chat or just chat with your keyboard. What you do is sign up for an account on Evolve at Evolve Home Page (opens new window) then download the client. (Also, this client can work on other games for hosting servers, such as Terraria, Steam Games, and even PSP games that supported Adhoc mode. (A good example is Monster Hunter 3 Portable.) 

Step 3: Getting your friends:
Once you got Evolve, sign in from the client, and then start getting friends to download the client too. Once that's taken care of, go to the Friend window and select the dropdown bar and click "Create Party". Once that's done, go into the party, invite your friends, and chose the game. (Minecraft in this case)

Final Step: Server Time!
Once all that is done, start up the server (Easier way, start up LAN on the world) then tell your friends to join the server (they can copy the ip)
(or if you're using a LAN world, tell them to check their LAN world list)


And that's how to make a easy Minecraft Server in just 4 steps! Thanks for reading, don't forget to Subscribe, diamond, and favorite!