Best Graphic Design Tips for Security Service Websites?

You should sit down with company stakeholders and find out what THEY expect from the website. They may have strict guidelines about which fonts, colors and branding you can use to ensure customer recognition of their identity.

What happens behind the scenes is every bit as important as how the site looks on the outside. If the site isn't secure and fully functioning, it's useless as a website.  Talk to your clients about their expectations.  Enumerate their objectives and priorities in a written contract before you begin.

WEB GRAPHICS:

• Use Adobe Illustrator to create math-based vector graphics and export them to SVG for the web. 
• Use Photoshop to create pixel-based raster images and export to WebP, JPEG or PNG for the web.

WEB SOFTWARE:

Adobe has exited the consumer web software space. They moved Dreamweaver to minimal maintenance status in 2021.  Before that they ended their other web products -- Muse, Brackets, Business Catalyst, Contribute, Edge and GoLive.  😞 

Use your favorite coding tools or site building platforms. There are dozens to choose from depending on what you need.

If you want recommendations, let me know.

Good luck.

I'd stick with "serious" colors such as black and gray, maybe a touch of red to suggest alarms, and the font matters too. A substantial blocky font that suggests strength etc. If the company name has a word in it that you can turn into an icon, that can be useful (like Firefox's fox etc). Any icon or shape that suggests strength or power is good. ADT's logo is in the shape of a Stop sign, which subconsciously suggests "Hold it right there, Buster!" 

-edit typo

what design principles or Adobe tools do you recommend for making a security service website stand out?

By @Exuberant_society5364

Since this is not a question about how to use Photoshop, I've moved your post the to The Lounge community.

Jane