I will show you the three ways I know to fly in KoboldKare.
The Three Ways to Fly
First Method: Fly With The Flycam Grabbing Yourself
Look down and grab yourself by pressing shift then the first mouse button then change to the fly cam and do not stop holding the mouse button.
This will allow you to fly free to any direction and at any speed if changed with the mouse wheel.
Second Method: Jump In A Object You Are Grabbing
Grab a Item with Shift + mouse click and hold the mouse button, with the mouse wheel get it closer and below you and start pressing the jump button.
This will allow you to fly fast but only upwards.
Third Method: Grab A Item Set It Far From You And Collide It To The Ground Fast
Grab a Item with Shift + mouse click and hold the mouse button then with the mouse wheel move it to a fairly far distance and then look down as fast as you can so the object collides with the ground and because you are grabbing it you will get launched up, to control it when you get closer to the ground move the mouse to the closest surface as fast as you can to get launched up again.
This method is not flying is more like big jumps but achieves the same!