Hi
Well a place to talk clicker were people do not think I am crazy.
Yippy. Do you know how many groups for yorkies I have been in that think I am right out to lunch training in a gentle manner. If you can not alpha roll or make then do it then you know not that which you speck.
To answer some of the questions.
A pen click or a tongue click is ok for a click.
Also a word yes or a made up word is better so it not said be accident, will work to but a click is better.
A toy can be use a a reward my girl works for a ball and food but I tend not to click if using a ball I just toss it at the right move on her part.
You can start any age of dog but the owner usually was a harder time not talking and luring. That be me as I am a cross over trainer working on fixing an aggressive dog that got hurt before I got her.