Ride Your Bike
For every 255 spaces you move, your egg gets one step closer to hatching, and a bike travels much faster than you will on foot. You can obtain a bicycle in after saving Rad Rickshaw from Team Galactic in Eterna City. The bike has two settings: third gear and fourth gear. Third gear is slower and allows for more accurate turning while fourth gear is for pure speed. Fourth gear will allow you to hatch your egg as fast as possible. Press "B" to alternate between gears.
Pokemon Abilities
Every Pokemon has one or two special abilities that assist it in or out of battles. If you have a Pokemon with the ability Magma Armor or Flame Body in your group, your Pokemon egg will hatch twice as fast. Pokemon with this ability are rare in "Pokemon Pearl," but the easiest to obtain is Magcargo in Stark Mountain. Magcargo is the most common Pokemon to appear in Stark Mountain, which can only be accessed after defeating the Elite Four. Magcargo will have either Flame Body or Magma Armor, which ensures that the first one you catch will be helpful.
Bike Path
When riding around at fast speeds on your bicycle, it is important to find a long, straight stretch of road where you will be free of interruption from wild Pokemon. There is no better place to ride your bike than Sinnoh's Cycling Road directly south of Eterna City. Simply walk onto the bike path and ride up and down the path.
Egg Cycles
Egg cycles vary between Pokemon species. An egg cycle is a set of 255 steps. The fastest Pokemon to hatch is Magikarp, which only has 6 egg cycles, or 1,530 total steps. Most Pokemon have 16 or 21 egg cycles, but some can have as many as 41 egg cycles. There is no set pattern for the number of egg cycles a Pokemon will have, but the general trend indicates that the more common a Pokemon is, the lower the number of egg cycles it will have.