Can you make a spell jar at any time or it’s good to wait for the right days or moon doing certain spell jars ?
In my opinion, you only need to wait for certain moon phases, astrological timing, or other timing things if you want to. They can add extra power to your magical workings but they aren’t necessarily required for them. This means that you can do a spell jar basically whenever you want.
I agree with @MeganB. If I need it now, I do it. If it can wait, I do it “on phase.” Here’s a phase guide.