wget https://github.com/FPille/OCRmyPDF-AppImage/releases/download/continuous/OCRmyPDF-8.3.2-x86_64.AppImage
chmod +x OCRmyPDF*.AppImage
./OCRmyPDF*.AppImage --help

Beside OCRmyPDF additional command line programs can be run with this AppImage like:

ghostscript
img2pdf
pngquant
python3.6
qpdf
tesseract
unpaper

Just use the program name as first parameter plus options:

./OCRmyPDF*.AppImage tesseract -v
tesseract 4.1.0
 leptonica-1.76.0
  libjpeg 8d (libjpeg-turbo 1.3.0) : libpng 1.2.50 : libtiff 4.0.3 : zlib 1.2.11 : libwebp 0.4.0 : libopenjp2 2.3.0
 Found AVX2
 Found AVX
 Found SSE

Or create a symlink for the corresponding program:

ln -s OCRmyPDF*.AppImage tesseract
./tesseract --list-langs