When you select Deadly Gift as your active skill, a menu should pop up showing the available traps (as Joram said you need eggs for spider mines, sacks of explosive powder for trail bombs and scorpions for scorpion traps). Left clicking one of these icons will set that as the trap to use, after which you should be able to right click on the ground to create the corresponding trap, as long have the available material.
Yes, Restoration is handy for any character (you can also get a couple skill levels as quest rewards).
Free skills, and spell books you can buy
