Step 17: Assembly Step 6: Soldering the First Part
On the PCB bottom bend the component leads apart – this will hold the resistor securely when you turn over the PCB to solder it on.
To solder, touch the component lead (wire) with the soldering iron and the solder wire at the same time. Surface tension will pull the solder into the via holes automatically. Add enough solder so it completely fills the hole and leaves a small “hill” of solder. Remove the solder wire and the soldering iron but don’t move the board before the solder has become completely solid again. The solder joint should be shiny and bright. Repeat for the other lead.
Check the topside of the board – you should see solder protruding a bit from the via holes – this shows the holes are nicely filled with solder (see picture below):