The #1 most important thing is to contact the right person at the company, the decision maker....
Check the company exec team on their website, Google, Bloomberg, Yahoo finance etc and find someone who can make the call on whether to buy the name (ie the business development manager, CEO etc). For example, If you Google "Cisco Executive team" for instance, it comes up with this -
https://newsroom.cisco.com/exec-bios, so its not hard to find the right person. If you Google "Cisco Email format", it comes up with this -
https://rocketreach.co/cisco-email-format_1063
So its not hard figure out the person's email either. I find LinkedIn a very useful resource for this.
For smaller companies that may not be in Bloomberg or Yahoo Finance etc, sometimes you can google something like "company name CEO" or look on LinkedIn and then find the persons name and then work out the email from there.
This is just what works for me
1) Email end-users with a short to-the-point email offering your name
2) Ensure you have a decision-maker in the company, DONT just use the WHOIS email, most of the time it will get ignored/deleted - Use LinkedIn, Bloomberg, yahoo Finance, Company site, Google etc to find out who the CEO, Business Development Manager is and contact them directly
3) Be patient, they dont always reply straight away (if at all) - Don't flood them with emails if they dont reply
4) Be polite and professional at all times, thank them for their time if they aren't interested, you never know if they might need/want the name later on.
5) Use Escrow for sales, it provides them with a level of security when dealing with someone they dont know, especially if you have contacted them first.
6) Send an email after the Escrow transaction asking them if they have the name in their account, thank them for their time, wish them all the best in the future etc...I think politeness and professionalism goes a long way in this industry, especially with the all the scammers online these days
Hope that helps, good luck