Hello jimkess,
Ensure the surfaces you're going to solder to are clean and free of solder.
You can remove the plastic base as suggested by smijesh to give your iron
tip more room to maneuver.
Melt a small amount of solder on only ONE of the pads. Let the solder solidify.
Align the capacitor over the pads to be soldered, making sure that you leave
some gap between the ends of the pads.
Apply heat to the solder you placed prior to, at the same time aligning the tabs
of the capacitor. Once solder has adhered to that single pad, allow it to cool.
Make sure the cap has stuck. You can now solder the other end.
I hope the above helps.
Please let us know how you get on.
Regards,
Relayer