[Items]
Berries:Pomeg,Kelpsy,Qualot,Hondew,Grepa,and Tamato [Extra]Poffins
Vitamins:HP Up,Protein,Iron,Calcium,Zinc,Carbos
Held Item:Soothe Bell
[NPC's]
NPC's:Massage Lady in Veilstone City,Ribbon Syndicate in Resort Area
[Others]
Others:Walking 256 steps,Battling,Level Up
And a quick note,riolu only evolves in the day time.
Hope this helps :)