Guide to correct use of grammar and punctuation, with exercises
https://www.ole.bris.ac.uk/bbcswebdav/courses/Study_Skills/grammar-and-punctuation/index.html#/
(University of Bristol)
What proofreading is, with checklist
https://www.sheffield.ac.uk/academic-skills/study-skills-online/proofreading
(University of Sheffield)
How to proof-read your work effectively (PowerPoint presentation)
https://unihub.mdx.ac.uk/__data/assets/pdf_file/0025/187540/ADAPTED-How-To-Proof-Read-Your-Work-Effectively-New-Format.pdf
(Middlesex University London)
Key steps in proofreading
https://www.port.ac.uk/student-life/help-and-advice/study-skills/written-assignments/proofreading
(University of Portsmouth)