Yeah, there was a discussion a while back about how to do that using various fabrics, or even bits of Venetian blinds, but the OP says his tire never goes above 35 psi, so it’s not an issue here.
You Tube is OK, but what Jtrops suggests -putting all spokes on the hub as a first step- is not on any of the You Tube videos I saw, even though it is what allowed me to build such a good wheel on my second attempt, using a full set of brand-new spokes.
My first attempt was just like what you describe. Every few weeks, PING! For more than a year, I diligently replaced each spoke as needed, thinking my wheel would mellow out over time, but it never did! Since I rebuilt it again following Jerry’s tutorial, though, and got its spokes nice and tight, my wheel has never uttered another peep.