The lifted increases are worked from the previous row/s by lifting up a stitch and knit/purl it.
LLI = Left-leaning lifted increase
As a knit stitch
Lift the stitch two rows below the stitch just knit from back to front onto the left needle, and knit it through the back loop.
As a purl stitch
Lift the stitch two rows below the stitch just purled from bottom to top onto the left needle and purl it.
RLI = Right leaning lifted increase
As a knit stitch
Lift the stitch directly below the first stitch on the left needle from back to front and place it on the left needle, then knit it.
As a purl stitch
Lift the stitch directly below the first stitch on the left needle from top to bottom and place it on the left needle, then purl it