1. Search for the name of the software on Google [2].
2. Open link to software in separate tab.
3. Open Wikipedia link (usually on the same SERP) for software in separate tab.
4. Compare domain name from direct link with the domain name from the Wikipedia article.
5. Open another tab and type domain name manually.
6. Find download link manually on domain[3].
I do this since a family member got burned badly by a malicious OpenOffice install many years ago.
[1] Sometimes I do it on Mac too, because the App Store has it's own issues (e.g. upgrades are often cheaper if you buy software directly). On any other system I use the package manager. All of this makes the effort bearable because I only have to do it rarely.
[2] I'm usually on DuckDuckGo, but for this I always used Google. The reason is that I had hope that they'd remove malicious results quicker. It's manual work after all and Google has more resources. This whole thread makes me doubt though.
[3] I'd do this anyway because I usually don't want to install the version that is automatically suggested, but decide myself which specific version I want to install. Most of the time the reason is the language.