1. Handwritten composition scanning: First, you need to scan your handwritten composition into a picture or a PDF file with the scanner or scanning App on your mobile phone.

2.OCR conversion: You can use OCR (Optical Character Recognition) conversion tool to convert scanned pictures or PDF files into editable electronic documents. The Windows operating system comes with OCR tools. If you use MacOS, you can use the pre-installed preview application for conversion.

3. Use a virtual printer: You can quickly turn a handwritten composition into an electronic manuscript by virtual printing without any tools. Take Windows system as an example, you can find "Microsoft Print to PDF" virtual printer in the equipment and printer options, so that the system can directly convert handwritten composition into PDF file.

4. Handwriting board and OCR: Another method is to use handwriting board and OCR software together. Input articles directly on the handwriting board and convert them into electronic manuscripts with OCR software.

Please note that the above steps are for reference only, and the actual effect may be different due to differences in equipment and software.