The use of Sivir in this way is too easy: just stay in the bushes and bully the enemies with Q and auto attack. Important is the use of E, it wastes the enemies abilities and let your adc attacks in easy way. The items, i choose, permit to run away from difficult situations or approach far enemies, because Sivir abilities can't heal or shield our mates XD.
I don't put runes, because they will be free and there are notes for the masteries.
I choose Sivir for a casual situation, but she worked very well. It's beatiful the testing of champion out of their role, don't let lol begin a static play, there are many beatiful things to do in Lol: testing is beatiful! I hope u enjoy the guide and test this anormal situation.
Finally have fun and sorry for my english.
P.S: hope u enjoied read this little and noob guide, give me feedback if u try :)