LittleBlocks is a mod that allows you to polish up your creativity and optimize your redstone systems. Indeed, the size of blocks placed in a little blocks is divided by eight compared to its original size, so you can place 512 blocks instead of one. Be careful though with the size of your creations because the resources (memory, gpu / cpu …) increases proportionally with it.
To place Little Chunks (blocks inside of which you can place Little Blocks) you have to use the Little Wand and right click like if you placed a block. The wand as multiple modes it can be used in (create, rotate, copy (only in creative) and destroy). To switch between modes you have to press a key that you can choose inside Minecraft’s controls panel.
When the Little Block is placed, your cursor selection becomes smaller to where you placed it. You can now place any type of block in it. The Little Block extends automatically when you exceed the size of a normal block.
About the Redstone, you can connect a Little Redstone circuit to a normal Redstone circuit by using a RedTorch or a Repeater else you could get an error. An other thing that should be good to know is the sides of a Little Block act like an OR Gate (if you have one or more RedTorch activated on the LittleSide, the normal Side will be active too).