Mage/Tips
Especially When it comes to casting True Magick, a player should keep in mind that it is fundamental reworking of the rules of reality based on a character's will. Thus, there is no cosmic force filling in the blanks for the character. For example, when a character casts a Correspondence/Entropy/Time spell to find the 'greatest threat to the city,' the result is completely dependent on the character's understanding of degree or importance. If it is the most property damage and loss of life, there could be a meteor strike in 2143, but there's really nothing mages can do in game about that. However, they could prevent the Sabbat Invasion of 2027, if they start working now. The more understanding the character has, the sharper result.
Sorcery and psychic powers are less flexible, but even they will benefit from having a clear idea of what they are trying to accomplish.
This suggestion doesn't only apply to the different forms of magick. There are very few requests more frustrating for staff than an investigation or research job where the players asks "I want to learn everything I can." Staff can be made to feel that they are being placed into a position where they are either misleading a player or doing all the work, and this is a collaborative game.