Soldering multiple resistors in series
You don't mention exactly what kind of resistors they are, but for "normal" through hole ones the best way is to first wrap one resistor's leg around the other resistor's leg, then wrap that resistor's leg around the first resistor's leg.  So you end up with this:



The resistors hold themselves together and make it really easy to solder.  It's a tough connection that won't easily break.

Depending on the kind of wire you're using you can use the same technique.  It's also common to "insert" the resistor lead into the middle of the strands of stranded wire for soldering.