Just today, by pure chance, I put together a little board with 16 SMDs LEDs, practically the same as these. I think they're the same size.
I just used some decent perfboard with plated through-holes, ran a line of solder paste down a row, placed the LEDs and resistors in place (touching where they need to) and then used my cheap Chinese hot air station to reflow it all. Then I ran a bit of thin bus wire to power it and tada! Works perfectly. The plated through-holes wick up all the excess solder, so you don't get shorts even on the heatsink pads. (The 2.54mm spacing of regular perfboard works well for devices around 5mm long like these.)
That said, I only did it for fun. There's little reason to build these yourself when you can just buy LED strips ready made.