Just finished my first proper board soldering job

Mine was one of those Velleman kits with about 40 resistors and a couple of ICs, and I made almost the same mistakes. My iron was an old Radio Shack one with no temprature control, so I was basicly guessing at the heat. The tip was also beat up from years of automotive wiring, and I didn't realize how much that mattered untill I put a fresh tip on and suddenly the solder flowed instead of sitting there like a pebble.

The dull joints thing took me a while to figure out too. Turns out most of mine were dull because I was moving the part around while it cooled. Started holding everything dead still for a few seconds after the solder flowed and they came out shiny on thier own. The braid trick for cleaning up bridges is something I still keep in my kit, though now I mostly just drag a clean tip between the legs with some flux and it clears right up.

One habit that helped me was doing the lowest profile parts first, resistors, then sockets, then anything tall, so the board stays flat against the desk and parts don't fall out when you flip it. Soldering a socket instead of the chip directly saved me from frying anything too, which was a real worry with my soldering skills at the time.

Funny thing about the dull joints. Mine stayed dull no matter how many times I redid them, and it turned out I was using lead-free solder, which just never shines like the old leaded stuff did. I spent a whole weekend chasing that mirror finish before a guy at my local club looked at my spool and told me to stop worrying. These days I judge a joint by whether the solder soaked into the pad and hugged the leg, instead of sitting on top like a little ball you could flick off with a fingernail.

My first board was one of those light sensor kits, and I killed a pad outright by leaving the iron on it way too long while I fumbled for the solder. After that I started counting in my head. Touch the iron to the pad and the leg together, feed the solder for about three seconds, pull everything away, and move on. If a joint still looks rough, I let it cool completely before going back to it. Going back too soon was how I lifted pads in the first place. One small thing that helped more than I expected was a little tin of paste flux. The kit solder has flux inside it, but dabbing a bit on the pads first made the solder flow where I wanted instead of beading up next to the joint.

What worked for me back when I was learning was keeping a scrap piece of perfboard and a handful of junk parts on the bench. Ten minutes of throwaway joints before touching the real board saved me a lot of grief. Old habit from my TV repair days, we always warmed up on the junk chassis first.

One thing I still do is hold the board up to a light after I'm done and check every joint with a cheap magnifier before applying power. A bridge you can't see at bench angle will jump right out backlit like that. Caught many a hairline short that way over the years.