Touchstone has met with Jaques again after having had conversation with him before. His greeting is a kind of blessing bestowed on Jaques for the pleasant conversation had on the other occasion. Touchstone is expressing his great delight in meeting his new friend again and being very amiable about continuing their friendship (and telling him he may keep his hat on: "be covered").
Good even, good Master What-ye-call't: how do you,
sir? You are very well met: God 'ild you for your
last company: I am very glad to see you: even a
toy in hand here, sir: nay, pray be covered.