I think I got a pound and a half of silica gel for around $7-$8. I put a tablespoon or two into a small coin envelope, then staple the flap closed. When I used up the first jar, I bought another rather than start baking the stuff to dry it out again.
Eventually I will bake both used-up batches. But I wish I could leave them int heir paper coin envelopes when I do! But even if the paper doesn't scorch at 250 F, the glue will probably melt.
I rely on small "humidity cards" with several colored dots to tell me the humidity on the inside of containers. If a packet of silica gel can't keep the RH below 30%, it's time to replace it.