The first thing is that "marketing" vs "PR" is a choice about where you think investment will be most successful. They're complementary rather than in conflict. PR is top of funnel, marketing is lower down.

It depends on the size of your start-up, but here's a method I've used with success for PR and new markets.

My first bit of advice goes against the article. It depends on how 'distant' the new market is from your existing market(s) but I think you should hire a PR agency. The press is different from the east coast to the west coast USA, the British press (more snarky generally) are different to the USA press and those all share the same language - if you're trying to break into an Asian market as a North American startup it's tough (and vice versa) as you don't understand the culture, the process and don't know the people.

Like any professional hiring, PR agencies vary so finding one with the skills and the fit is key. Find a couple that work in your area (e.g tech and b2b or b2c), you can do this by looking at stories from your target market from tech firms and seeing who the PR agency is plus going to some industry events and personal contacts. Select three agencies and ask them to pitch a six month plan - then select the one you think will work. It's generally best to work with an agency where you are important to them, and where you have a consistent team that gets to know you. Work closely with the agency so they understand you and you them - they are representing you after all!

Second bit of advice is understand the news/PR situation in that market. Essentially, the articles advice is to find the right sources and journalists for your start-up - that totally makes sense. The agency should be able to tell you about each news location, what they focus on, who the journalists are and what they focus on. Then look for news and ways you can relate to their objectives. One advantage that you have is that you're new and an outsider which brings a different perspective: ultimately this is what journalists and news sources need, something original and different. A good way to do this is each month pick a theme/idea and pitch that to a section of your news contacts - if you have a PR firm that should be the main way in which they help.

Ultimately, this is the key you have to have something new (so pick an angle) that journalist can use to get published (so make it easy for them) that the news source thinks its' readers will care about (so target subjects their readers care about).

Consistent cadence is important, someone else made the point that it's a "marathon not a sprint" (one of my favourite phrases). Developing a reputation with a publication for being interesting and 'giving good copy' helps. For a new market it could take six months to get any sort of interest and really up to a year before you'll be well-known enough to get consistent coverage. The team has to invest in the market, CEO has to physically go there to meet journalists (as a normal part of opening up that market). PR should just be one element in the general plan for opening the new market (e.g. events, sales, analysts, marketing, pr, hiring etc).

My last comment would be know when to withdraw. It's possible that there just isn't a good PR approach in a market, because it's focused in a particular area - for example, I personally found doing PR in Taiwan difficult because we were software and the entire market is focused on the hardware space so the only coverage we could get was our commentary on the hardware space which didn't achieve anything from my perspective. Try a few different cycles with the PR agency, network with other companies to see their approach and if it doesn't work put your investment into a different approach or market.