These are some resources I recommend. Some of the below I benefited personally from and their content has informed this guide.

David J. Keuler, PhD. When Automatic Bodily Processes Become Conscious: How to Disengage from ‚ÄúSensorimotor Obsessions‚ÄĚ

The above is a classic and gives a really nice overview of what SOCD is.

Dr Seay’s series of posts on the topic.
Part 1:
Part 2:
Part 3:

This is very detailed and he makes many good points. On the third post, you can actually see my posts from way back in 2012, when I was struggling myself and asking Dr Seay questions!

Hershfield & Corboy, The Mindfulness Workbook for OCD, Ch 14 – Hyperawareness OCD

This chapter on hyperawareness OCD covers more than just body-focused obsessions, although the principles are generally the same. Some good coverage of common thought patterns, triggers and obsessions.