You are never done exploring this breathtaking island. But, to give you some inspiration for your trip, I have written down the itineraries of two journeys to Iceland. Note that these are road trips and contain a lot of driving. I haven’t done a lot of hiking myself, so these routes are not described. Do not let that stop you from including them in your trip.
Road trip in 15 days, Ring road
The first trip would be the first trip I made to Iceland, after which I learned a lot for the next trip. It is a 15-day trip around the Ring road or the 1, and it includes most of the touristic highlights and Dog sledding at Snow Dogs. Check out the itinerary here: Road trip, 15 Days
Roadtrip in 18 days, Icelandic Coastline and Westfjords
The second trip is an 18-day road trip alongside most of the Icelandic coastline. The goal of this trip was to spot puffins and visit the magical Sea-monsters in the Westfjords. Which, in hindsight, I need to visit again next time. Check out the itinerary here: Road trip, 18 days