Can anyon please teach me how to create a keylogger and how to send it through Skype so i can get my runescape account back.

A key-logger is a program that will log every stroke of the keyboard. The log can then be reviewed in order to steal passwords or simply monitor the computer use such as in the case of a parent checking up on their child's activities after the fact. Most spyware detection programs will detect a key-logger unless it is installed by the computer's administrator. So the only way to sneak a key-logger onto someone else's computer is to bundle it with other software so that it is set up at the same time. You can do this by downloading a legitimate software package and modifying its installation program.
**Warning: It may be a violation of the EULA to modify software. Instead, you can write a batch file named install.bat which will install the key-logger and then the software or the software and then the key-logger, whichever you think will be less noticeable. A batch file is simply a text file containing the commands to execute at a DOS prompt, with each command listed on a new line.

It will also be easier for you to download an existing key-logger rather than write your own. You will also need some sort of "back-door" program installed so that you can retrieve the log file, unless the key logger is designed to upload it automatically.
In order to send this to your friend via skype, you will have to tell them it's some really kewl wares and that they should check it out, so that they will download and install it. You cannot just put something on someone else's computer; you have to trick the administrator or user into accepting the download and into running or loading it afterwards. If they did this to you in order to steal your runescape account, then you will not likely be able to trick them in the same way.

Keep in mind that "stealing" back your account may be considered just as unethical as stealing one in the first place, and may be unlawful in some jurisdictions. You are the only one responsible for knowing and obeying the laws in your area. This answer in no way constitutes assistance to commit a crime and shall be considered null and void in all jurisdictions which hold it to be a crime. This answer is meant only for lawful use.