(RPG MV) How to create own tilesets? Tutorial?

I've just bought RPG Maker MV and am really excited to get to working on my game, but I want to make my own tilesets and don't know exactly how and what the sizes are or where I need to be putting where and why. It's all very confusing and though I have experience with RPG Maker before I've never attempted at this. Please help in guiding me! What do I need and how do I do it. (Also excuse me for I'm a new comer on this site)

Hi and welcome :)

You can find details of the tileset formats in the help file (F1) under the Documentation > Asset Standards heading.

You can also take a look at the default tilesets to get an idea of their content and naming.  

With the B-E tiles, they're all the same - same size, and treated the same way in the editor, so those tiles are interchangeable.  Not so with the A tiles.  Each one is a different size and the tiles on it are all formatted differently.  They also MUST go in specific slots when you pull them into the editor.

Oh! Thank you very much! I was confused at first and had already read inside the MV Help folder and found everything, I was only confused about the A tiles. Thanks!