You’re shipwrecked on a chilly island in the Pacific Ocean. It’s not one of those places they make movies about where the sun shines down on the sandy beach. Not for you. Your beach is covered in snow, ice and no doubt there will be some sand down there too when the Spring thaw comes along. For now, it’s really cold.
You have food, water (tons of that with the snow to melt) and shelter (you found an abandoned cabin someone must have built and forgotten). So basic things are covered, other than the hope of being found any time soon. You have pen and paper and not much to do but spend your time writing and keeping warm.
Think about where you are, your surroundings, the sights, smells and sounds around you. Write a description starting from where you are sitting and gradually heading outwards to end at the deep ocean. Or, begin somewhere far from where you are and describe inwards to where you sit under blankets scritching over the paper with your pen.