I'm doing two things in 2018:
Trying to improve my lighting knowledge.
Doing so with stuff I already have.
I've spent countless hours reading and watching gear reviews and I've slowly, thanks to my cognitive impairment, begun to realize that none of those do anything to improve skills, and they do a lot to convince me that I need to spend money. Instead of wasting my time feeling unsatisfied with my gear, I've decided to spend that time finding inspiration and learning to create things I'm happy with.
Shoot through umbrella I got this at Calumet in Philadelphia before they closed all their stores. It came as a kit with an umbrella, a reflective umbrella cover, a light stand, and an umbrella bracket with an adjustable coldshoe. It's nice enough. The umbrella is ultra lightweight and therefore pretty fragile. The stand is decent. Sturdy and very tall, but with no cushioning, so you need to be sure to tighten it well.
ExpoImaging Rogue 3-in-1 Flash Grid This is just a universal sleeve that fits a speetlight, and a holder for honeycomb grids. It comes with two 45˚ and 25˚ grid disks that you can use independently, or combined to yield a 16˚ spot. It gives you a round spot with smooth edge fall off.
ExpoImaging Rogue FlashBender Reflector with Diffusion Panel Essentially a white that mounts to your speedlight. The thing that makes it cool is that it has flexible rods embedded in it that allows you to bend it to any shape you want and it will stay. It also has a diffusion panel that attaches with velcro to soften the output, like a tiny softbox.
FStoppers FlashDisc Tiny circular diffuser that slips onto a speedlight to turn it into a 12" round softbox. One side of this disk is translucent diffusion material, and the other side is tri-color opaque vinyl, white, gray, and black. I'm assuming the back could be used for setting white balance, but I don't actually know that its panels are pure white, pure black, and 18% gray. It folds up into a small pouch (included) that would easily fit in your pocket if your pants aren't too tight.
It's really convenient and requires only a couple seconds to set up. If the speedlight you're using is a big one you may struggle a little getting the elastic cuff over the flash. The only downside is the price. I got four of them for $100 when they first announced it a few years ago, and gave three away as gifts. The current price is $49.99 and I think that's way too high. I like FStoppers, and I would prefer to buy theirs, but not at four times the price of the imitations from China.
Octabox 80cm with diffusion panel and egg crate grid.
This thing opens like an umbrella and has a deep parabolic shape. It's nicer and more durable than my shoot through umbrellas, because the parabolic shape requires that the bows flex more, so they're some kind of composite and they don't kink like the cheap metal ones in the umbrellas.
I absolutely do NOT recommend this thing because it's an inherently flawed design. The light stand passes through an opening in the bottom of the umbrella, and then you pass the center rod through the umbrella holder on the stand. All that is fine, however, the diameter is pretty small, so when you mount the speedlight in the coldshoe of the bracket, it is so high above center that you can't avoid a hot spot in the upper portion of the softbox. Also, you want the light as far from the back of the parabola as possible to maximize spread, and you achieve that by having the stand as close to the end of the center rod as you can. Unfortunately when you do this you can't tilt the umbrella so that it points downward due to the size and location of the zippered opening.
If you want something like this, get one with a Bowens mount, double diffusion, and a grid. That way you can use it with a studio strobe or with a speedlight in a Bowens mount adapter.