F2L

F2L (First Two Layers) means solving the first two layers at once: instead of corners and edges separately, you join them into pairs and insert each pair into its slot. After the cross, four slots remain, each holding one pair: a corner and an edge in the colours of the neighbouring faces.

Intuitive F2L doesn’t require learning algorithms. There are three steps: 1) find a pair (a corner and an edge that match by colour), 2) connect them on top so that they touch and have the same colours on the sides, 3) insert the connected pair into the slot with one move or a short insertion (R U R', F' U' F).

Rules that help: don’t break what’s already solved, so take a pair out with a move that comes back; use the top layer (U) to line the pair up over its slot before inserting it; if a corner is in the slot and its edge is on top, take the corner out to the top and start over. When the same case comes up again, your hand will remember the solution.

Below are 41 cases of a single slot (front right corner, white face on the bottom, yellow on top) with ready algorithms, for when intuition fails or you want to be faster. Every case can be solved intuitively; the algorithm is a shortcut. You do the other slots with the same algorithm after rotating the cube (y) so that the slot is at the front right.