Tip #1 - Assess Relative Heights
This is almost always my starting point when working with groups, regardless of whether I'm planning to shoot them standing, sitting, or kneeling (or all of the above), because it helps me begin to pre-visualize the best way to fit everyone together.
Normally I have everyone line up shoulder to shoulder, and then I'll just rearrange the group members until I have the shortest on one end and the tallest on the other. This lets me know exactly what I have to work with in terms of height, and gives me immediate insight into the best posing arrangements to use during the shoot.
Tip #2 - Make Triangles
If I had to pick just one technique in this entire list to learn, this would definitely be the one. It's one of those things that once you learn how to "see" it, it'll become second nature, and your group photos will improve quite noticeably.
You'll also begin to recognize this technique being applied in other photographers' work, whereas in the past you probably wouldn't have been able to put your finger on exactly why a particular shot just worked so well-- why it seemed so harmonious and balanced.
So here's the tip: try to arrange your group members so that if you were to draw imaginary lines between their heads, you'd end up with little triangles everywhere.
Another way to create triangles is to simply switch your group members around until you don't have two people of the same height standing next to one another.
Anyway, I think you get the point......triangles are your friend. I use this technique in almost every single one of my band photo shoots, and I recommend that you keep it in your back pocket as well.
Tip #3 - Use Props
Sometimes no matter what you do to arrange your group members in a visually pleasing manner, you just can't seem to find anything that works well. For these situations, you might need to get a little resourceful. Look around for anything in the area that you might be able to use artificially "adjust" one or more of your group members' heights.
I've used items such as rocks, tree stumps, and sidewalk curbs when working outdoors, and when I'm in the studio I always keep footstools and small blocks of wood around for this purpose. I'll even break out my wife's step aerobics equipment on occasion...that stuff actually works great!
Another great source of props to use for posing group members is furniture-- couches, loveseats, ottomans, and the like. I've found that when people have something to sit or lean on, it allows them to relax more, and they'll often fall right into a natural-looking pose with minimal effort.
One day while location scouting I came across a small trash dump, and I immediately noticed that several of the items looked like they probably came from the same home. I thought to myself that it might look kinda cool to rearrange the furniture into sort of a "homeless man's living room" and use this scene as the backdrop for a band promo. Fortunately, when I pitched the concept to one of my clients, they really dug it.
Tip #4 - Watch the Hands!
In the realm of portrait photography, more photos are ruined by poor hand & arm placement than just about any other factor, in my opinion. The reason is simple-- when posing for a picture, nobody ever knows what to do with their doggone hands! This especially true of men, and since you'll most likely encounter more males than females in band photography, you really need to know how to deal with this issue effectively.
The easiest approach is quite simple-- if you can't get your subjects' arms & hands into a position that actually adds something interesting to a photo, then do everything you can to take the focus off of them. To accomplish this, try the following:
1) Crop - Whether you do it in-camera or in post, try cutting your subjects off at the forearm or middle of the upper arm (be sure to avoid cropping at the elbows or wrists, however).
2) Control your light - Use grids, gobos, and other modifiers to direct the light onto your subjects' faces and upper bodies (and NOT on their arms/hands).
3) Adjust exposure in post - Use the graduated filter and/or Adjustment Brush in Lightroom. In Photoshop, you've got a number of options including: dodge & burn, blend modes like Darken or Multiply, Curves, Levels, etc.
All of the above methods will help you get around potential issues with hand/arm placement, so feel free to experiment and find what works best for you. With that said, I certainly don't want to suggest that you should simply run away from this challenge altogether. Doing so will severely limit your creative options, and eventually your band photos will all begin to look the same.
What I recommend doing instead is to tackle the issue head-on, and spend some time learning how the masters approach the issue of posing their subjects. There are numerous free and paid resources available online that will help you shore up your skills (YouTube is an amazing resource).
And if you're specifically interested in posing bands, you really need to check out my eBook, 10 Essential Poses for Band Photo Shoots (and How to Set Them Up), which will walk you through my own personal methodology. It'll help you immensely when it comes to putting your subjects at ease and taking command of your promo shoots.
Tip #5 - Fake it in Photoshop
Sometimes you'll find yourself in situations where no matter what you do, you just can't seem to get all the group members locked into a good pose at the moment you press the shutter. You might succeed in getting almost all of them looking like rock stars, but there will be at least one person who just absolutely ruins the shot.
Other times you might have lighting limitations that prevent you from getting an even exposure across the entire group. You try shifting people around, bunching them together, and adjusting your subject-to-light distance, but nothing you do seems to work.
Or maybe what you saw in your mind's eye before the shoot just isn't coming to fruition in front of your camera. You can't seem to get the angles right, or perhaps you don't have the necessary props to adjust the group members' heights . You begin to wonder whether capturing such an image in-camera is even within the realm of possibility.
For situations like these, there is often only one solution-- Photoshop. For example, in the shot below, I wanted the group members to be perfectly spaced, evenly lit, and about the same height. Could I have accomplished all of this in-camera using the techniques discussed above? Sure. But it would have taken me much longer than the roughly 10 minutes I spent in Photoshop to create the same result.
These are all techniques that I've picked up over the past 7 or 8 years of shooting band promos, and I'm sharing them with you now in the hopes that you can apply them immediately in your band & group photography for much better results.