In CyberSphere, there are several blades that can be obtained. Anything from your basic utility knife to a Katana. To use your blade you simply need to be holding it in hand. We will use a Katana for example.
DoughBoy rushes at you brandishing his fists, you decide you're going to slash him up with your katana. So the first thing you would need to do is make sure you have that Katana in your hand. This can be done by using the command: 'wield Katana' or 'hold katana'.
Most blades in CyberSphere allow you to customize your technique with a slash or stab. The command is basic: 'slash with katana' or 'stab with katana'. Once again when in doubt of what you can do with your weapon or any object for that matter, use the 'exam <object name' for a list of verbs that apply to the object in question.
Oh yeah, thieves... they can steal from you, taking your nice new Katana without you even knowing, If they're good anyway! So you may want to find yourself a Back Scabbard for your sword or a Knife Sheath for your Knife!
(courtesy of Peter Brady 7/21/99, all typoes his)