Usually used in conjunction with "nizzle", both words where invented by rapper Snoop Doggie Dogg. Instead fo saying what was used until then, "Fo' sure, my nigga.", he created the phrase "Fo' Shizzle my Nizzle"
"Dude, did you get the tapes?"
"Fo' Shizzle my Nizzle."
The Skidoo part comes from a town. In 1906, two prospectors got lost in rare Death Valley fog while enroot to Harrisburg. They stumbled across gold-bearing ledges. The town of Skidoo formed around this area and in 1906 the Skidoo post office was opened. By 1907 Skidoo had more that 500 residents. By 1917 one mine is reported to have produced 1.5 million in gold. Today no structures remain, only a few fallen buildings and the ruins of the stamp mill as well as a few graves. The "28" part may refer to something significant the town provided for the rest of the world. Soon, It became a nonsense saying popular form 1920 to around the 50s.
"28 Skidoo" (28 Skidoo is usually proclaimed to be silly or funny.)