If you're setting up a specific quest for a typical group of adventurers, you probably need to spoonfeed them exactly what the quest is, unless you want them to jump to all sorts of wild conclusions that only relate tangentially, if at all, to what they really need to do.
Even Gandalf did it. He told Frodo exactly what to do at each step. Take the Ring and meet me in Bree. Follow Strider (to Rivendell). Come with the Fellowship to Mordor. Let's go through the Mines of Moria...
Of course it still went off the rails when Frodo decided to ignore Gandalf and head off into the wilderness with Sam. Let that be a warning to GMs everywhere.
GM: R2, you've recovered from your stunned state.
R2-D2: Right. This wedding stuff is all very nice, but we're forgetting the most important thing here.
[SFX]: < ding-whree-eeroo bippity boop-pip-deep ta-zing pow >
Leia: What's that?
R2-D2: Did we recover the Lost Orb?
[SFX]: < deep-dooby ping boop-deep-dooby bibizung >
GM: Where are you looking?
R2-D2: Threepio! Ask Wedge if he can detect the Lost Orb up there. A big power source.
[SFX]: < po-fipgi-doip-bedoop pating meep-zung-doip deep-dooby bibizung fodooby bebespip >
Wedge: Scanning, good buddy. Nope, not picking up anything like that.
R2-D2: That's not right. It's a mythic level artefact. It can't be destroyed, except possibly by one very specific means which would take an epic quest to achieve. It's got to be somewhere amongst the flotsam.
[SFX]: < bloop bebebespip pow boop-poppity boppy bebetong boop-deep-dooby doodle-pow >
Chewbacca: Don't forget who the rightful owners are.
[SFX]: < doop ping >
C-3PO: The Gungans, silly!
Chewbacca: And Naboo was destroyed. The Orb may be truly masterless now.
Luke: Ooh! I know what our next quest is!
Luke: The Last Gungan!