A good way to to do it is to take your hat and beat it against your leg in a back and forth motion,This is done rapidly.While you are doing that you do a series of excite putt' s.You can use a mouth call wich is easier because your one hand is busy with the hat motion,With some practice you can do it with a push button call,But you have to be able to hold the call and operate it with one hand.
It kinda sounds like--Start with hat And call-putt putt putt putt--putt putt-putt-Stop with hat, Silence for a few seconds,Then start with a few putt' s, Then go into a yelp sequence.
During the few seconds pause after fly down you should put your hat back on so you can set up quickly.
I hope this help' s you
It' s hard to explain by typing it out.
Good Luck To You