The next step is to permute the corners within their respective layers. This step is exactly the same as PBL on 2×2. There are 5 cases (plus 3 mirrors, but I’ll leave it up to you to mirror those cases. Recognition is easy: each layer either has solved corners, an adjacent swap, or an opposite swap. That is, either solved, J, or N. Find both layers and execute the correct alg.
The easiest case is N/N. solve it with /3,-3/-3,3/. It’s the same as R2F2R2 on 2×2.
Next is the most common EP: J/J. Position the solved corners on B and solve with /-3,0/3,3/0,-3/.
Third to learn is N/J. Put the solved corners of the J on L. Then it’s solved with /3,0/-3,0/3,0/-3,0/ Think of it as a double sexy move but with R2s.
Next is J/solved. Put the bar on R and do /3,0/-3,0/-3,3/-3,0/3,0/
Finally there’s N/solved. This is done as /-3,-3/3,0/-3,-3/3,0/-3,-3/
Just do yourself a favor and learn all of these, plus the mirrors of N/J, J/solved, and N/solved. They’re all easy and it’s a pain to do 2look.
You’re almost done! The final step is Edge Permutation.