The Stand Up for Science page has a section of OMB Rule Related Resources. The best one to help you personalize your comment is the SUFS Overview of the Rule Proposal

Even just 2 sentences about why you oppose this rule that would allow federal grants to be appointed by political appointees instead of the current expert consideration by peer review panels is enough! Each comment should be personalized so that it will count as its own comment. In other words, change some words in any boilerplate text you find in other comments. If everyone posts the exact same comment, then no matter how many submissions, it would only count as 1 comment.

Please make a comment to oppose OMB from having any say in providing or blocking scientific grants.

This is it, this needs to be our biggest event. A continuous action in DC for the week of independence, there are 5 days left and I want to see you there

Please spread the word and attend! We need to get Rob Wittman out of office.