minecraft how to format a giant command

                                  How to format a giant command

                                           begening
/summon Item ~ ~4 ~-0.1 {Riding:{id:MinecartCommandBlock,Command:fill ~-1 ~-2 ~1 ~1 ~ ~-1 minecraft:air,Riding:{id:MinecartCommandBlock,Command:kill @e[type=Item,r=4],
       put more commands here. format them using Riding:{id:MinecartCommandBlock,Command:  put command here,

                                              end
Riding:{id:MinecartCommandBlock,Command:setblock ~ ~3 ~Riding:{id:MinecartCommandBlock,Command:setblock ~ ~ ~-1 minecraft:lava 5, Riding:{id:MinecartCommandBlock,Command:kill @e[type=Item,r=4], Riding:{id:FallingSand,Time:1,Data:0,TileID:157,Riding:{id:FallingSand,Time:1,Data:0,TileID:152,Riding:{id:Item,Age:5996,Motion:[0.0,0.0,-0.1]}}}}}}}}}