You want to feel like you have done nothing yet everything at the same time, your bubbles protect your homies just as much as they create kill opportunities. Your W is great early game to stack your item and keep you and your ADC in lane longer, even after ganks and retreats to tower. Your E is great for starting an engagement, as the ADC goes in, use E and they'll be able to create a longer-lasting engagement (they'll be less likely to run away) and the E is also great for chasing for the same reasons.

As Nami, you can be brutally murdered in milliseconds and so yu must play behind the team, keeping away from poke and possible damage. Although you are playing safe, you still want to keep pressure in lane and go in with your ADC, just keep your priority to use abilities to buff instead of getting within auto attack range.

Ill be updating this as I gain more experience playing this champion. If you disagree or would like to see changes in the guide please comment and let me know.
Enjoy your Nami gaming!