The cross

Four edges around the bottom centre, planned in inspection.
The cross is the four edges of one colour placed around their centre, each also matching the side centres. Every cross can be solved in at most 8 moves; good solvers plan all of it in the 15 seconds of inspection and execute it on the bottom, so they can look for the first F2L pair while turning.
A solved white cross on the D face (white bottom, yellow top); the rest is unsolved.
R U R' U F' U' F U2 L' U L
The daisy: the beginner's cross. The white edges sit around the yellow centre; each is turned down onto its centre with a half turn.
F2 B2 R2 L2
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    Solve it on the bottom, not the top: you see the F2L pieces sooner.
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    Plan the two hardest edges first; the last two often fall in with the moves you need anyway.
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    Colour neutrality (picking whichever colour's cross is easiest) saves moves once you are comfortable with more than one colour.
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    An X-cross solves the cross and an F2L pair together: a typical step for advanced inspection.