What process do you use to purchase cables?

I’m in the process of updating my gear and thinking about what to do for updated cables. Every time I think about it, my head spins as there are so many different cable options & companies. I struggle to even start the process.

I don’t care if it’s speaker cables, interconnects or power cords – Just explain what you typically do to nail down your purchase.

FYI – my past “process” was to simply purchase whatever I found to be the most affordable options recommended by folks on this board. For that reason, I’m currently using Canare 4S11 speaker cables, Mogami Gold interconnects, and Pangea power cords.

Since I’m planning to push my component updates to significantly higher quality gear, I don’t want to fall short on the cable side. If you have a process, let’s hear it! Thanks

If I have 3’ interconnects that make my system sound nice and warm….if I reorder a 9’ set of the same model does that mean my system will sound 3 times as warm?
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For me the process in which I have the most confidence is to work with my dealer and audition various cables.  If I did not have access to a dealer with good cables from which to choose I would take advantage of The Cable Company loaner program.  In my opinion the components of a system are like ingredients in a recipe and for me, I have to listen to them to make my decision.
Short of buying cables at the dollar tree, I’d say most are a safe bet. Me, personally I prefer UK built and engineered cables of a modest price. In fact, most of my components are built and engineered in the UK. I happen to think that the UK produces the best sounding gear. Sugden, tannoy, whardedale, Linn, Ear, Rothwell, Graham slee, origin live, goldring, chord, Atlas, qed, ecosse, just to name a few...
Find a widely known brand that is associated with very high end systems, carried by upper end dealers and be willing to spend a few thousand. Also, talk to manuf and describe your system. They may advise beyond cables. 

Initially try cheaper cables $500 or so for mains and center. I now use these in other systems i have. 

breakin periods, availability, etc make it diff to borrow and test 

 I have transparent super cables, and they are very good.

buy on faith and have patience during breakin period.