It’s best to avoid the Strip in a car anytime, but especially at prime times -- after 7 every night and 24/7 over the weekends. The shortcuts run parallel to the Strip (north-south) and across the Strip (east-west).
Your best alternate north-south route is Industrial Road, which runs parallel to the Strio on the west, across I-15. You can cross the freeway to access the Strip from various points, from W. Hacienda (delivers you right to the Mandalay Bay parking garage) up to Sahara. North of there, you can make a quick dogleg on Wyoming (right) to Main Street (left) and continue north all the way to downtown.
On the east side, you should learn the Koval-Paradise parallel route from Tropicana to Sahara avenues. Go east on Reno Avenue (it intersects the Strip between Luxor and Excalibur), then follow it around to the north (left) onto Koval. You can hit the back doors of all the casinos on the east side of the Strip, from the MGM Grand to the Venetian. Where Koval ends, do a dogleg right (east) on Sands Avenue, then left on Paradise, from which you can access the entrances to all the casinos from the Stardust to the Stratosphere.
Crossing the Strip on east-west thoroughfares can be brutal. The fastest way to get from one side to the other without touching it is to make use of the three-mile Super Arterial, which connects Paradise on the east to Valley View on the west via the six-lane no-lights Desert Inn Road. This shortcut is extremely convenient if you’re going from the Orleans, Gold Coast, Palms, or Rio to the Las Vegas Hilton, Hard Rock, MGM Grand, Riviera, and Sahara.
The second best option for crossing the Strip is Spring Mountain Road (west) and Sands Avenue (east) between the Fashion Show Mall and Treasure Island. Spring Mountain Road is often five times faster than trying to cross the Strip at Flamingo Road. And it’s only a long block away, the next large street over (north).
Tropicana Avenue is also preferable to Flamingo for crossing the Strip.
