If you have money, DEFINITELY start a blog. I learned everything I could about on-page SEO so that I’d have the numbers to back up ‘SEO expert’ on my resume.
I picked a niche, and got to work on content. No social media or promotion. Now it makes a full time income (albeit a small one) so now I can be much more selective with the jobs I take.
Apart from the (pretty much passive now) income stream, starting my own site has really given the confidence to apply for jobs I wouldn’t have dreamed of applying for a year ago.