Instructions
Press "Start" and select "Pkmn." Rearrange your Pokemon lineup so that Gible is in the first position. This will ensure that he is used automatically at the start of every battle and gain all the experience from that battle.
Battle trainers and wild Pokemon to gain experience and level up. Trainers and wild Pokemon can be found all over "Pokemon Pearl," normally along the various routes leading from town to town. The amount of experience for Gible to level up varies for each level, but is noted underneath his life bar when battling.
Gain enough experience to reach level 24. Gible will then evolve into Gabite.
Gain enough experience to reach level 48. Gabite will evolve into Garchamp, the final evolution of Gible.