Help for create New Graph Templates

[paradoxi]

Hello

I am newbie in Cacti.

I would create new Graph Templates for my switch, i would like to have in one graph thier informations :
Unicast Packets / Traffic (Unicast Packets div Traffic) but i have already rrd source for traffic and Unicast Packets by port. How to use these sources in new graphs ?

Can you help me for create this Graph Templates.

Thank you very much.

Ps: I am very sory for my poor English