My block center consists of 3 shelves of resources. Train tracks and blocks stay in year round, while the rug and accompanying resources change based on our current theme. We use the Melissa and Doug rug sets shown below in our block center.
I attach labels to my buckets and shelving using velcro dots from Amazon. I always place my velcro the same way (1 dot in the center of each end of the label) which means I can easily peel off unused labels and stick new ones on without issue. My labels each contain the word and photo for each item.
Directly above my block center are booklets hanging on the wall that display 2d and 3d shapes. These booklets are often changed out when we change themes for booklets containing structures specific to our current theme.