The building confidence bit is perhaps peculiar to the very young. We of great age may be good at many things, but if we do them for pleasure, it is not so much for the purpose of re-building confidence, as it is for pleasantly practicing long mastered skills, while doing something useful.

I bake, or weld, or service an engine, or play my guitars, or garden, or sharpen my knives, not so much to prove to myself that I can do something useful well, but because I like pie, and want my machines to work, and like the sound of a vintage Martin, and the smell of flowers and trimmed grass.

Hmm, I am a Jill of many trades, master of none. I am fairly good at cooking, sewing, gardening, anything domestic. Cleaning my bathroom can make me feel better about myself. :)

Maintaining positive relationships increase my confidence and happiness level. This week I was feeling a little blue, a little blah. Yesterday I met up with a couple of friends for a couple hours, it was a great pick-me-up.

Running gives me confidence. A few years ago I started a running program and could barely run for two minutes. At the end of 12 weeks I was running five miles without much difficulty. Achieving something that I thought I couldn't gave me a lot of confidence. Plus, running or exercise in general is great for the mental health.

Age gives me confidence. I am a lot more confident now at 34, versus ten years ago.

Jill of many trades

I like that phrase--a lot!

I've discovered that I'm not really good at anything, though I'm adequate at a great many things. This would be fine if I didn't actually want to be good at a couple.

I agree with what PaulSC and LoriFLA say, in general.

Confidence-building is a necessary activity during early adulthood, which is why it's good to accept all sorts of challenges and try things you never thought you'd be interested in. Confidence can only come from experience followed by reflection - the experience doesn't even always need to be 100% successful or pleasurable, just something you live through and, as a result, develop new strengths. Relying on strengths you know are there builds confidence.

I'm good at writing, making songs, singing, wordplay, cooking, triathlon training, setting and achieving goals (whatever they may be, it's still a skill), hiking, talking in front of groups, organizing, analyzing, remembering detail, learning, and researching.

I'm passable at gardening, drawing, socializing, performing, home repair, sewing, light carpentry, sailing, rock climbing, and guitar playing.

I kind of suck at team sports, mathematical thinking, major construction, baking bread, and being patient.

Writing, acting, dreaming, poetry, making people laugh, interacting with animals and children and wearing things.

I'm also good at lifting weights, being silly, learning new languages (I speak five semi-fluently), and assessing wines.

Hrm.

I'm good at calming people down, making friends with cats, playing bridge, most team sports, remembering names, cooking, mediation, mentoring and SCIENCE!

I like but am not good at running, writing stories and swimming. I don't care that I'm not good at these things, because they make me happy.

I'm good at making friends with children and animals.
I'm good at writing.
I'm good at finding things out.
I sing pretty good.
I make a fantastic pig grunt noise.

I excel at swallowing, urination, and sitting on the couch.

I putter.

If I'm feeling down I tend to just do something I enjoy, regardless of my skill at it. I either go for a walk (I'm fairly good at that) or go out and take pictures (same thing as a walk, only you bring a camera.)
It gives me something to do, and takes my mind off of whatever is bugging me.

I am very, very good at making very, very bad decisions.

I whistle really well.

I excel at stressing over nothing
watching television
napping
selling encyclopedias

(I also have no confidence and am fine with that.)