Welcome in the forum!
Well, and how will you limit the current? When there is a limit of 100 mA per side you ought to limit the current.
And: Use bredboards, no solder, easy changing!
Thanks for the welcome. (Good idea to use breadboards. I'll get some.)
The resistors are chosen to limit the current. I know the voltage, so I just choose the resistors such that I = V/R < 25mA per pin. And connect up at most 4 pins of course.