As there are many different picking techniques, and any number of chord inversions, there are different strumming patterns for guitar. A list of strumming patterns is nearly impossible to define, as there are variations from jazz patterns all the way to country strumming patterns (and every style in between) that go well beyond the usual guitar strumming patterns. As many players as there are, you can be assured new strumming guitar techniques, as well as guitar strumming tricks will be invented to challenge the old patterns. Learning guitar chords strumming or just the basics of strumming the guitar could take a few months, but years to master.
Basic strumming patterns is where this all starts. Down strokes or up strokes, it is imperative you keep the rhythm steady (unless of course you want a slower or different strum on your opposing direction). Sometimes within the same stroke you might slow down or speed up, but these are beyond the basic strumming patterns. In fact there are those basic strumming patterns where you don’t even attempt opposing down-strokes and upstrokes, just a nice steady flow with a flick of your wrist in one direction.
No matter what stroke you are trying, what level of skill you have, the motion with guitar and strumming should come from the rotation of your wrist. Overall it is best not to stiffen your wrist stiff when strumming (even picking).
There are some differences in strumming a guitar, based on the type of guitar you play. Strumming patterns for acoustic guitar can often become very percussive; there is a lot of bouncing off the strings. In some ways the acoustic makes guitar strumming tricks easier and the flourishes you manage might seem very showy because of the big sound you can get by moving your wrist fast across the acoustic sound hole. But at the same time, placement of your hand is very important when trying various strumming patterns for this type of guitar; no matter how you are strumming the guitar you get the best results by playing directly over that sound hole.
Guitar strumming techniques for electric can be different, but basically it is still up to how well you move your wrist…and where you strum. The pick-ups in an electric guitar (or an acoustic with pick-ups) allow you to play at various places over the body of the instrument. Strumming the guitar close to or away from pickups, even choosing to play over one pick-up instead of another alter the sound of even the most basic strumming patterns.
As a magician might claim, it really is all in the wrist”. By regulating your speed during guitar strumming, adding some guitar strumming tricks like hammers and pull-off’s, and even actually lifting your hand from the guitar, you can introduce whole new strumming patterns into your playing. The trick really is to keep the motion consistent and your wrist placed correctly (and your pick held tightly (if you are using a pick). The dexterity and speed you will gain in practicing a good steady strum will help you even as much or more so, then the scales you can run off. There are a bunch of good lead players out there, in fact almost everyone who picks up an electric guitar wants to play lead, but how many players do you know even know the most basic country strumming patterns, or how many of us can keep up a consistent, odd timed rhythm through an entire song?
Guitar strumming is a basic of playing the instrument.