To add a slave you need to crack the password of a NPC/Player until you have admin access. Once you have admin access you will be able to upload/download etc and the computer will appear in your slaves list.
My slave has gone!Edit
You can loose your slave if the computer owner changes their password, this usually happens every so often with NPC's so make sure you check regulary.
The next step from adding a slave is to start uploading an installing virus's, you have three virus choices. Each better than eachother, if you chose a spam email the amount of spam sent would depend on the computers speed and the virus's version.
Large virus's may also take a long time to upload but will be resistant to earlier forms of antivirus. Once a virus is installed you will need the appropriate software to control it.
- MarketingMailer (version of your virus) - Spam
- RemoteControl (version of your virus) - DDOS
- FTPCash (version of your virus) - Warez
Once your virus has been working, you can then access the slaves list, select your slave and click collect income. Or you can use the Collect Income from All Slaves link.