To install BeebEF, unzip the zip file in any directory with the option 'use folder names' enabled.
Then you have to decide whether you want have your emulator disk filing systems (DFS's) controlled by BeebEF or not. BeebEF comes 'installed' with two DFS roms: a normal DFS and an E00 DFS (which keeps page at &E00--handy for tape-based programs). You can have BeebEF automatically install the right DFS for every program you run in an emulator.
To have BeebEF control the emulator DFS's.
To always use the already installed emulator DFS's.
Note 1. The DFS's in the BeebEF directory 'DFSRoms' are the default Acorn 1.2 DNFS rom and the Solidisk E00 1.2 DFS Rom. You may change these for any DFS roms you like, as long as you use the right file names: 'DFS.ROM' and 'E00DFS.ROM', respectively.
Note 2. For the E00 DFS to work in any emulator, the emulated sideways RAM/ROM socket into which the DFS is loaded needs to be set open for write operations! For the emulator PCBBC this can be done by giving the PCBBC DFS rom the extension '.RA?', where ? needs to be filled in. (See Setting up emulators for use with BeebEF.) With the emulator BeebEm, the option 'Allow rom writes' has to be selected manually after running it.