Any way to transfer iTunes songs to iPhone?

Hi everyone,

So I've had a series of unfortunate events occur and am a bit stumped on how best to go about correcting them. I updated my iPhone to whatever the most current software is (7 maybe)? Then I tried to transfer some iTunes songs to my iPhone, but it said that in order to be compatible I had to download the newest version of iTunes. I thought this was a bit off since iTunes usually prompts me with updates already, but I did it anyway and updated. The only problem was that when I tried to install the new iTunes, it said my iMac was too old. I'm using Mac OS X version 10.5.8. Bought my iMac in 2008. I had it optimized and when given choices for memory, etc. I chose the best of everything because I wanted it for the long haul. It still runs fairly well for a six year old computer. But now I'm in this conundrum.

I'm wondering how best you'd recommend remedying the problem. Is it easier to backtrack with iTunes or iPhone? Is there another method by which I could play music on my phone? (I know next to nothing about cloud storage so I'd need some help there). Anyway, your input would be much appreciated. With some tech things I'm excellent and with others I'm rubbish. This is clearly the latter.

Many thanks for your help.