Free Redaction Software

[Merlin]

I'd use the redaction feature in Adobe Acrobat. Since you don't have a copy, you may not realize that you can get the whole Adobe suite for $19.99/mo using the Adobe Creative Cloud student discount. That includes Adobe Acrobat Pro. For $20/mo, its a pretty decent deal. I think it only lasts a year (or maybe only a year after graduation) but either way, it's worthwhile if you use Adobe products at all, which I do. After the year it goes up to $29.99/mo, which is still a pretty good deal.

If I had to do it for free, I'd check out the free PDF editors (or ones with a free trial) to see if any of those support native redaction. There has to be one that can be used without a CC.

Failing that, I'd load the PDF into my graphics editor (there are plenty of free options here) do the redaction, and then save (or print) the file out as a new PDF. If your graphics editor doesn't natively handle PDF, then you can always view it on your screen and do a region/screen capture to an image file and then go back to the editor to do the redaction.