An excellent "how to" article from Scientific American.
As both a scientist and a writer I would add a caution pertaining to this part of the article:
At the same time, science is knowledge of great human benefit. Because of the way we pay for it, that knowledge rightfully belongs to the public. The job of a science journalist is in part to simply take that knowledge out of the area of professional communication and science meetings, and make that available to the people. In that sense it is cheerleading. Some science writers are also advocates for investment in science institutions and prioritizing science knowledge over other kinds of knowledge or argument in public debate, and in that sense you can see what science writers do as an explicit form of cheerleading. But the important thing that the scientists, science writers and public have to remember is that scientific knowledge, is always conditional; more research can lead to different answers than the ones we report today. So even when you are cheerleading you have to remember you may not be right.
While the cautions are appropriate, I'm very uncomfortable with the "journalist as cheerleader" mindset. That is the job of editorial writers, not journalists.
In fact, some science writers believe it is their role to "advance the narrative" on topics like global warming. Take this example from a science journalism blog:
The take home message is this: It’s not just the responsibility of scientists to reach out. It’s also on science journalists. And we need more skilled, credible, and honest storytellers doing their part to get the narrative right–particularly on topics like climate science, vaccination, and energy. Having a science background is an asset, not a hurdle for this trajectory. [emphasis hers]
"Get[ing] the narrative right" is what propagandists do, not journalists! Yet, several of the members of that group do indeed believe their job is advancing the "narrative" of global warming (scroll down to the comments).
Just this week we saw the media across this nation highlight two stories that attempt to "advance the global warming narrative" even though the climatological facts do not support the "narrative" in those cases. Links to the two stories are here and here. With regard to the former story about Greenland, even those in the pro-global warming camp believe the story, as written, is nonsense (two examples here and here).
My suggestion to science journalists is to be just that: Journalists. It is a noble, essential profession.
Addition: This is a perfect example of being an advocate/propagandist rather than a journalist. It is quite unlikely that the current heatwave and drought are tied to global warming.