Lock the slide back and insert a pencil or your finger into the mag well from the top and push down the black thingy (that is hinged from the back.) Pull the slide back and align the witness marks on the slide and frame. Then remove the slide stop. The slide then slides forward off the frame. Push on the guide rod assembly from the rear to compress the spring a little, lift it up and out of the barrel notch, and out of the slide. Then slide the barrel slightly forward and lift it up out of the slide by pulling it slightly up and to the rear. Reassemble in reverse order. Insert an empty mag into the gun and remove it (this pushes the black thingy back into position). Then check for function.
Sorry for the use of the highly technical terms (thingy) but I haven't seen or touched my KP95-DC in years! It's buried in the back of the safe somewhere.
Good Luck,
Savage
edit: Of course you could also go online and get any information on the Ruger that you need, including an owner's manual in PDF format.