I suppose you clicked on this because you are an aspiring Minecraft network owner. Well this is your lucky day. I will be teaching you how to do this, but first, I will explain what a network is. Just to get this out of the way, yes it will cost money, but you will also be able to make money in the long run through donations.
A network is a group of servers that are all connected through a plugin like BungeeCord or Lilypad. BungeeCord is a proxy, connecting multiple server together. That means that you can run multiple Spigot servers (link below) and transfer players between them. A player would only connect to BungeeCord, and he doesn't notice which Spigot instance he is playing on or whether he changed the servers. This is especially useful, since Minecraft servers are single-threaded. If you use BungeeCord and multiple Spigot servers you can use multiple threads (and thus multiple cores of the server's cpu). In conclusion, you still need one or more Spigot servers, but users connect to BungeeCord instead; thus the API is different, as it has to do different stuff. Most work should still be done on each server. The point of making a network is to spread the players, plugins, and worlds across multiple servers to limit the amount of lag that naturally occurs when your server has too many players/plugins. Spigot Information
Usually, a starting network will have 3-4 servers so that:

• 1 Server is the BungeeCord proxy (The server that redirects players that join to the specified server)
  
• 1 Server is the Hub/Lobby
  
• 1-2 Servers are the actual gamemodes that your players play on (Factions, prison, skywars, etc.)
  

I suggest using this host to purchase your servers as they offer cheap, reliable hosting for all of your network's needs.
https://www.beastnode.com/portal/aff.php?aff=4137

Creating a successful network might sound challenging, but if you follow my directions carefully, then you should be well on your way to becoming one of the most popular network owners in the history of Minecraft! (Not really, but nothing is impossible ;))
To get a better idea of how this works, study this picture below.

The BungeeCord server located in the middle of the picture represents the BungeeCord proxy server. On this server, you install the BungeeCord plugin and edit the config file to include your servers (not going to make that tutorial unless I get requests to do so). After installing BungeeCord and configuring the file, you're done with that server for the rest of your life! Not really, but you will rarely ever come back to it unless a plugin requires you to do so.

So now that you have created the heart of your network, you'll need the 2-3 servers that you purchased from a host (link above).
Now is the time to decide what gamemode(s) you will want for your network. It can be something completely unique, it is up to you.
After making a decision on what gamemode(s) you'd like on your network, you will need to build a Hub/Lobby spawn on your Hub/Lobby server. You will want to make this build look as appealing as possible because this is going to be the first thing that players notice when they join. If you are a good builder you are in luck. You will be able to create a nice-looking spawn for your Hub/Lobby server. If you are a challenged builder like me, you can purchase or download free builds from various websites.

After you have completed the Hub/Lobby server, you can get into the fun stuff! With the leftover servers that you've purchased, you can make them into whatever gamemode you would like. There are endless amounts of opportunities here, so let your creative mind run wild! Some examples of common gamemodes include:

• Factions
  
• Prison
  
• Skywars
  
• Skyblock
  
• Minigames
  
• Survival
  
• HCF (Hardcore factions)
  

Some standard plugins that I suggest you download which are completely free are:

• Essentials
  
• WorldEdit
  
• WorldGuard
  
• A permissions plugin such as Groupmanager or PEX (PermissionsEX)
  

With each gamemode, you can add your own creative touch to it to make it a unique and enjoyable experience for all who get the chance to join your incredible network. For example, you could make factions into "OP-Factions" or prison into "OP-Prison". Making a gamemode "OP" simply means that the items that you give players and that players can obtain are ridiculously overpowered compared to regular vanilla items (Sharpness 10, bedrock bases, custom enchantments, etc.)
I cannot stress this enough, THE MORE UNIQUE YOUR GAMEMODES ARE, THE MORE PLAYERS YOU WILL ATTRACT TO YOUR NETWORK, AND THE MORE EXCITING YOUR NETWORK WILL BE. THERE ARE THOUSANDS OF FACTIONS AND PRISON SERVERS. WHAT WILL YOU DO TO MAKE YOURS DIFFERENT? That is up to you. Again, there are endless amounts of opportunities to create custom gamemodes, combine gamemodes, or even just add to existing gamemodes. Don't let ANYONE tell you that you can't do it, because only YOU can decide what you are capable of. That applies to anything and everything you do in life. DO NOT let others limit you and tell you what you can and can't do. Creating a network is a unique and fun experience, which brings you a ton of satisfaction after you complete this big project. This process will take time, so do not think you are slow if it takes you a while to set everything up.

There are a few things that I probably left out, whether it be on purpose or not. Please leave a comment requesting something that I forgot to include and I will be sure to answer as soon as possible. Also, I didn't include specific tutorials inside of this general tutorial, so if you need help advertising your network, setting up BungeeCord, Spigot, Buycraft (donations plugin), or other plugins, don't be afraid to leave a comment asking for help. I have a YouTube channel that I can post video tutorials on or I can make another tutorial like this one. My YouTube channel- https://www.youtube.com/channel/UCV8LTJ0Xm01QwG68ncCAFBQ
Thank you all so much for reading, and have a great rest of your day.

Side-note, click on this link if you would like to purchase or just create a free website for your Minecraft server (all successful Minecraft servers have a website)- http://www.enjin.com/?ref=3120188