All these methods will have some effect, but to work properly baffles should be firmly attached to the tank to prevent them moving. When the water sloshes about, it comes up against the baffles WHICH DO NOT MOVE and so the water is stopped (or at least slowed down) as it sloshes around in the tank. If the baffle material is loose inside the tank then all that happens is the whole lot (water and baffles) slosh around as one big mass.
DIY baffles should be jammed together as tightly as possible so they can't move, otherwise they do no good at all.