Ideal Off-Page Activities for Law Niche

If the firm has a google business acct set up.. you should be cranking out citations, and any amount of directories you can get your hands on.

Depending on what the lawyer may specialize in, and if they are willing to actually write.. guest blogging could be a huge plus.. but sending the stuff out would be a waste of time.

There is tons of bad advice on this forum - the blind leading the blind, as it were. Most of the things you have mentioned stopped working many years ago.

Getting high quality links starts with having something that is so good, people in related niches almost HAVE TO link to it. Infographics are definitely one of the things on your list that can work if implemented correctly with an embed code that links back to your website. Guest posting/blogging is the other thing that can work if done correctly.

Blog commenting and forum posting MIGHT bring you some traffic but dropping links in either type of place is not going to help you rank better. I would subscribe to HARO (Help A Reporter Out) and have them automatically email their list of questions reporters need help with every day. There won't always be law ones, but quite often there are. You can get some fantastic links in some pretty major online publications by providing answers to reporters' queries.

You should also check out Brian Dean's 2017 Definitive Guide to Link Building as well as his Backlinko Blog for ideas on how to get real backlinks that work.