AFK Runecrafting Methods in OSRS

At any Runecrafting level, you can craft runes at the Ourania Altar south of Ardougne.

If you're on the official Ourania world, you can use an item on a player that's running ahead of you to run all the way to the altar for an AFK period of around 25 seconds.

When crafting Astral Runes, if you have GPU mode active on RuneLite and extend your render distance, you can click almost the entire way to the altar, giving you an AFK time of around 30 seconds.

The most AFK Runecrafting method out there is Zeah Runecrafting.

When you're mining Dense Essence, it's possible to AFK for up to and over a minute at a time, although sometimes the rock depletes fairly fast, so a little bit of focus is needed.