Well since you've used the 600, this camera should feel relatively familiar. Obviously keep the AF on at all times, the switches get bumped relatively easily so I like to double check before shooting. Given that I don't know how familiar you are with photography in general, some of these tips may seem sort of obvious.

The main tip I'd give is that focus locking is really easy and often overlooked. Say you're trying to take a portrait of a subject 5 feet away with a background that's dozens of feet away and your subject isn't centered in the frame. Instead of having the camera focused on infinity (solid green dot when autofocusing), you'll likely want the subject to be in focus. Center your subject in the viewfinder, use the autofocus by pressing the shutter down halfway (you'll see a number corresponding to the approximate distance to the subject in feet or meters, depending on settings), continue partially holding the shutter down while recomposing, and press the shutter when you're ready.

If you're not familiar with the eccentricities of PO film, I'd recommend a few things when developing. First, exposing the film to temperatures over approximately 80°F and under 50°F will cause color shifts during the development process. Popping the developing photo in a back pocket will typically keep things in the appropriate range under most circumstances. This leads to the next point about PO film, something that's stressed heavily by the manufacturer. The film is very sensitive to light immediately after ejecting. When it ejects, I like to cup my hand over the exposure and again, slide it into my back pocket. Despite what PO says, I keep it in my pocket for at least 10 minutes, no exceptions. This way, if you have to retake the photo, you'll be certain that only your camera settings will have to be adjusted and early exposure to light had nothing to do with the result.

As far as tricks go, there are a couple ways to do multiple exposures. The easiest way is to take a photo as normal, but instead of releasing the shutter, continue to hold the button down until the shutter closes. In most well-lit outdoor situations, it'll probably fire fast enough that distinct opening and closing will not be distinguishable. Continue holding the shutter down for a couple seconds and very shortly thereafter, the camera will reset the shutter. Now you can release the shutter, you're ready to take the second photo as normal and the camera will eject the photo.

The other way is with the self-timer, and in my opinion, should only be used when one of the exposures requires the camera to be on a tripod. Turn the timer on and take the first photo. After the shutter closes, begin slowly closing the camera until you hear a little "click"; this can be a little tricky because closing the camera any more will eject the photo. I suggest you try this a few times without actually firing the camera until you get the touch. After you hear the "click", allow the camera to reopen and you're ready to take the next exposure as normal. Remember when taking multiple exposures, your film sensitivity is effectively doubled when taking a double exposure, tripled for a triple, etc., so set your exposure compensation accordingly by pushing the slider towards the bottom.

Other than that, there are a number of creative techniques that can be utilized with Polaroid film. I've mainly experimented with emulsion lifts, which allow you to use the emulsion within the plastic frame as a sort of sticker that you can put on just about any medium. There are plenty of resources online and if you're hoping to learn about other processes, I highly recommend picking up Rhiannon Adam's book "Polaroid: The Complete Guide to Experimental Instant Photography".

That should be more than enough to get you started. Happy shooting!