Used to hate this part. Buying domains on one site, setting up Workspace on another, adding DNS records by hand, creating users one at a time, then connecting everything to the sending tool. For 30 or 40 inboxes it would eat most of a day and I'd always mess up a record somewhere and find out a week later.
These days I order everything through the inbox marketplace inside the platform I send from, and I do it through their API instead of the dashboard. One request with the domains I want and how many inboxes per domain. It registers the domains, sets up SPF, DKIM and DMARC, creates the Workspace users with the names I pass in, and the inboxes show up connected with warmup already turned on.
For TLDs I stick to .com almost every time. I'll use .co if the .com variations are all taken but I stay away from .xyz, .info, .online and that whole group, a lot of them have a bad reputation with spam filters before you've sent anything. Domains are close variations of the brand, like getbrand.com, brandhq.com or trybrand.com, so if someone looks at the sender it still looks legit. I never send cold from the main domain.
3 inboxes per domain, real first and last names, profile photo and a normal signature on each.
For the split I usually run about 60% Google and 40% Outlook. If the list is mostly local businesses I push Outlook higher because a lot of them are on Microsoft 365, and if it's tech companies I go heavier on Google. Warmup runs 14 days before anything cold goes out, weighted across Google and Outlook recipients so it looks like real traffic, and it stays on after launch.
Once they're warm I cap them at 15 to 20 cold emails a day each and add more inboxes if I need more volume instead of pushing the ones I have.
Source: r/b2bemailing · by /u/Efficient-Length7655