Highly confused

[Matchstick]

I've read through the documentation and a number of the posts here, but haven't achieved enlightenment. I have 2 different OIDs that I'd like to place on one graph (as lines representing the actual polled data rather than averaging or any other aggregation function). This kind of data would then get plotted for various devices in my network, so templating all of it seems the right thing to do.

I tried creating various templates in various ways, but can't seem to make it work. What I thought I had to do was create a data template that used the "Get SNMP Data" DIM, then add 2 Data Source Item entries in the template with each OID. However, the 2 tabs which I get doing that can't seem to have different OIDs assigned to them. I'm very confused about which templates I have to create and which ones I don't. Affinities seem to be created that make the templates more specific (i.e. get assigned to specific hosts rather than staying generic until assigned to devices). Can anybody provide me with a useful run through of how I would create this kind of setup?