I have been climbing (lead-climbing/top-roping/bouldering) for less than a year now but after quickly improving for the first couple of months I have now reached a "plateau" as they say and I don't know what to do to improve.
I am aiming to improve especially my bouldering skills where I am still stuck doing V0-V1-V2 (UK grading).
Thank you for your help.
If you're not falling a lot, then you're not pushing yourself enough, ergo you won't see much improvement.
Grasping a basic understanding of proper climbing technique is what enables most new climbers to quickly advance in their climbing abilities, but once you have that understanding of climbing principles, then your limitations are mostly physical; you need stronger fingers and core.
If you're topping out at V2, then chances are you're still not very fond of holding onto anything that you can't fit all four pads on and sink up to your second knuckle, you need to get familiar with hanging onto holds that you think are just terrible, namely: small crimps, pinches, and slippery slopers. Most new climbers hate these types of holds, but that's because it takes training and experience in order to know how to approach them, how to hold them without injuring yourself, and what angle you need to hang onto them without popping off, this is where core strength is key, you need a strong core to keep you balance and hold everything together.
Although this question is rather broad, the general answer would be to spend more time at the climbing gym in the bouldering cave. You can climb a lot harder in the gym than you can outside, because it's a much more controlled environment, and you don't have to worry as much about hurting yourself when you fall. When I went outdoors I was more interested in toping out than I was projecting something hard, and spent more time finishing problems. If I couldn't get it in a few tries, I'd move on, but in the gym I'd project the same problem for months and some I'd only ever top out on once. Some I'd be able to piece together, but never be able to get all the way through them, and they'd eventually get taken down when the holds were cleaned and the cave re-set.
If you want to see quick improvement, you need to be constantly challenging yourself, and trying problems that are way above your grade, dedicated boulderers will spend absurd amounts of time trying to master a single move in a problem, they will train like crazy, with that one single move in mind. Case and point: anyone who has ever tried to climb "Lucid Dreaming" out in Bishop California, it only has two or three moves, but it's a V15 (downgraded from a V16, but the top-out is "only" a V7).
If you are in the V0-V2 range, the sure-fire way to get better is to climb with more volume and intensity. Here are some practical things you can do:
To complement the other answers, I'd recommend drills and climbing with handicaps. If you're climbing a route that's normally very doable, try it with a few variations:
Doing these taught me better technique, strengthened my core, and broadened my skill set. Skipping holds adds a lot of variety to a route, and forces you to not rely on the same technique all the time; for me it meant not relying on brute upper body strength, but developing better grip and legwork.
Also, be more observant of climbers around the gym. You'll notice people of different skill levels and body types that you can learn from. The biggest disclaimer is that not everyone has the same reach/strength/flexibility/explosiveness as you, but with those limitations in mind, your ability level will grow just from watching.
Personally, going from V2 to V3 was the hardest improvement to make in my 3 years of climbing. It wasn't until this point that I started to identify my weaknesses and took active steps to fix them.
