Here is what I've been planing for about a week...I hope I'm of some use! So, let us begin...
1. DO NOT use rare candies all the time. it does two unhelpful things: first, sometimes it doesn't give you many stat changes, and it gives you no EVs (short for effort values). EVs are attributes which give bonuses to a Pokemon's stats and improve differently depending on which pokemon it defeats. Therefore, only use rare candies when needed greatly.
2. If you trade a Pokemon to a friend with full happiness, it will start all over again with the new trainer. If traded back, the same affect will happen since the Pokemon became attached to the other trainer. Be careful if you always want your Pokemon to like you.
if you are the glitch/cheat type person, you may want to try these:
Pal Park glitch: makes it where you can migrate any number of Pokemon via the Pal Park. This is used to surpass the 6 Pokemon per every 24 hours.
GTS Level display glitch: In SOME copies of Platium, the levels may not be displayed on the GTS. To fix this glitch, the player must contact Nintendo.
GTS Morphing glitch: Causes Pokemon that's for trade to change it species and somehow hold a Seal Bag.
GTS Trading evolution glitch: In a Generation IV game (includes Pearl & Dimond, Platium, and Heart Gold & Soul Silver), if the player deposits any Pokemon into the GTS that can evolve though trade holding an item (for example, depoisting a Duskull holding a Reaper Cloth.), and either waits for over 24 hours before taken back, or trades for another Pokemon before taking the first back, the Pokemon will evolve after being recived.
And last but not least, The Black Belt gibberish glitch: For some weird and unknown reason, a certain Black Belt in Victory Road may speak glitchy gibberish upon being defeated.
Well, I hope these glitches and-uh-other information- helps you when needed.