First, find out what level of Hoardstalker you can summon, depending on your Summoning level. That information can be found here:
http://RS.wikia.com/wiki/Dungeoneering/Summoning
Now:
1. Start a dungeon.
2. Kill something and get a charm. The next step is to head back to the main room, but make sure you've gained some Dungeoneering experience before doing so. This
is important for the glitch to work correctly. (A good way to make sure is to complete around 50% of the dungeon. Just estimate.)
3. Once back in the main room, you need to create some sort of "Hoardstalker" pouch, and summon it.
4. Now, exit the dungeon by going up the ladder.
5. The Hoardstalker will be with you still. Now wait until it says "your familiar has found an item", or something to that effect. You can wait as long as you want,
the Hoardstalker will keep finding items until it's inventory is full. When you're ready to smuggle them out, go on to the next step.
6. Right click the Hoardstalker and choose "Take Item", but don't actually take the items from it. Close the "take item" window now.
7. Now, click on your Notes. With your Notes screen open, walk over to the little drop off that lets you back into the main castle area.
8. Click on the drop off and choose "Yes", and as you fall, rapidly click the "+" that lets you add a new note.
9. Once you hit the floor, don't move. On the Summoning Icon (beside the mini-map), right click it and choose "Dismiss".
10. Your familiar will be dismissed and it will drop the item it was carrying. Pick up the item, and voila. You've smuggled it out.
Your Welcome..
