The tile you settle on has a series of numbers. Grain/Materials/Essence. If you settle on a tile with 4/2/1, you have 4 Grain, 2 Materials, 1 Essence. That number is derived from the resources from the surrounding 9 tiles and added up to be 4/2/1 in this case. If you see a tile next to it with 3/2/1, that means the 9 tiles around that tile add up to be 3/2/1. 

This makes settling much easier to figure out since you won't need to do any complicated mathematical procedures to figure out which tile is the best to settle on. In general, You want a 4/2/1 or better to start on. Anything less that 7 total points and you may need to press Ctrl+N to remake the map.