SMD work

[akis]

I have watched a few youtube tutorials on how to work/solder SMD components.

Do I understand it correctly that the PCB must have a solder mask otherwise the solder paste will bridge ? On the youtube tutorials they use professionally made PCBs but for home made ones, I do not have solder mask equipment.

[Kjelt]

This might be an issue on components with small distances between the legs <0.8mm so or you can use a lot of flux and hope for the best or as I sometimes do with rework, is solder each leg seperately with a small smd solder pencil and a tiny amount of solderpaste (not solderwire but paste) that you have put on with a syringe with needle and  solder paste dispenser.
EDIT: I assumed you manually soldered, for reflowing the amount of paste is crucial, too much paste and small pitch even the pro pcb's won't stop bridging.

[sleemanj]

Do I understand it correctly that the PCB must have a solder mask otherwise the solder paste will bridge ?

Only if you were using really tight pitchpackages, or were sloppy with the paste I expect.

I don't reflow, but don't have problems with drag-ish soldering SOIC etc on home etched boards without mask, easy as pie.