Hi Maya Benoit,
Many thanks for your post.
Indeed, the project notes section is currently the main target for such instructions.
However, as this comes with a number of trade-offs by being a project-wide and not task-specific field, we're planning to add further functionality to include more specific and/or relevant instructions, and without having to repeat them constantly.
In the meantime, an available, alternative approach can be the usage of Custom Fields, to either directly include specific (task) instructions or link to an additional (site) location during project creation.
Best regards,
Phillip Maieski | Trados Product Management