Two options depending on the Weather at the moment.

1. Ring Road clockwise.

Start from Reykjavik. > Kirkjufell > Hvítserkur> Akureyri > Goðafoss > Dettifoss/Selfoss> Hengifoss> Höfn> Stokksnes> Jökulsárlón Glacier Lagoon> Svatifoss> Vik > Svatifoss (this are just a rough plan)

2. If the north part is not accessible I would concentrate on the south and east area. All the way up to Egilsstaðir and then back south.

Starting with two days in Reykjavik. Next stop Hof for one night and then all the way up to Egilsstaðir. From there I will be heading south west until I will be back at the Airport.