I was inspired by CNC workshops Urban grounds. I bought some cheap MDF and had it cut in squares of 30 by 30 cm. The tiles where covered with 5mm foamboard. Tiles without roads on it are covered completely, tiles with a straight road are covered on the sides, leaving the middle untouched. The roads are formed by the sidewalks. So it's easy to make T-section and corners. I made the roads a lot less wide than they are in real life. Otherwise they would be a deathtrap to anyone on them. Infinity is a very unforgiving game when you are in the open.
Then came the most difficult part. I was fortunate to have access to an engraving machine. With photoshop I made some designs and the machine engraved them on plasticcard. It took about 2 hours to make the surface of the 32 tiles. I realise that not everyone has such a machine but you can make the designs, bring them over to someone who has one (ie trophy shops)
The roads (not the sidewalks) then got a basecoat of black and where then airbrushed with grey in different layers, progressively lighter. The markings are airbrushed also. I made a template of cardboard, cut out some rectangles and airbrushed over it with white, leaving the markings on the roads.
The trees
These are simply essential for this game. In this game you cannot have enough things to block LOS. It also gives some colour to the predominantly white city. I bought them at Ikea and a pet shop. I cut the plants to pieces and glued them with a hot glue gun in bundles to a base ( squares of different sizes of foamboard ) afterward I painted the surface of the base with glue and I flocked it. In a few hours I made a dozen bases, so it goes very quickly and it's also very cheap.
The fences
These are made of plastic I got from cake boxes. They were simply cut to strips, glued onto a base and airbrushed.
Some cover: Hirst Arts, Urban War pipes and a cake box fence.