Unless you have a budget to conduct formal research, its best to use available resources such as news articles, industry journals, analyst reports, the company’s website, marketing collateral, company reports and so forth. You may also want to do a general blog search to find out what their customers’ and others are saying about the company and the products they offer. Networking events and tradeshows also present great opportunities to collect data about your competitors. Your more loyal customers may also share information with you.
Do they have separate marketing messages for different segments? Sometimes, you might see a stark difference between how your competitor markets their business for one type of customer versus how they present themselves to another type of customer. For example, if you're trying to sell services as a math tutor to high school students who are struggling to pass their math subjects, you'll be making a completely different pitch than you would to those students who need additional help with their SAT math so that they could get into prestigious universities. Your message to the struggling students might be closer to "I'll help you finally pass your math tests!" While your message to the other market will be similar to "I'll help you get into the school of your dreams!" Also, be sure to note if your competitor does something similar with their own customer segments.
When using the Keyword Explorer, Ahrefs will also produce the "parent topic" of the keyword you looked up, as you can see in the screenshot above, underneath the Keyword Difficulty meter. A keyword's parent topic is a broader keyword with higher search volume than your intended keyword, but likely has the same audience and ranking potential -- giving you more a valuable SEO opportunity when optimizing a particular blog post or webpage.