To solve a Rubik's Cube 3x3 step-by-step, follow this beginner's method:

  1. White Cross: Align the white edge pieces to create a cross on the top face. Ensure that the white centerpieces are correct and all cross pieces' colors match the centerpieces underneath.
  2. White Corners: Position white corner pieces to the top layer. Ensure yellow centerpieces align with the cross you've already made.
  3. Second Layer: Finish placing yellow edge pieces on the middle (second) layer, matching colors with the centerpieces below.
  4. Yellow Cross: Create a yellow cross on the top face, aligning yellow centerpieces on the bottom layer.
  5. Yellow Edges: Fix the yellow edge pieces in the correct locations, matching colors with the centerpieces on the bottom layer.
  6. Yellow Corners: Position yellow corner pieces correctly, but don't worry about orientation just yet.
  7. Orient Yellow Corners: Rotate yellow corner pieces to orient them correctly, such that their colors match the centerpieces underneath.

Each step may involve specific algorithms. Here's a concise guide:

  1. White Cross: Use R U R' U' R' U R'
  2. White Corners: U R U' L' U R' U' L (some cases may need repeating)
  3. Second Layer: R U R' U R U2 R' U R' U' (repeat until edges are solved)
  4. Yellow Cross: Position according to the case.
  5. Yellow Edges: Switch edges R U R' U R U2 R' U R' U'
  6. Yellow Corners: Position according to the case.
  7. Orient Yellow Corners: Use the R' D algorithm for all corners that still need to be oriented. You can also find online solvers such as Grubiks to guide you with a step-by-step visual solution.

Remember to keep the cube aligned the same way while performing these steps to prevent confusion. Learn and practice these algorithms, and soon you'll be able to solve the Rubik's Cube effortlessly.