Warming up an IP address with no recent sending history requires a gradual, consistent, and engagement-focused approach. Experts and documentation emphasize the importance of progressively increasing sending volume over a period of 2-3 weeks, starting with a small, highly engaged segment of subscribers. Consistent sending patterns are crucial, and large fluctuations should be avoided. The goal is to establish that the mail is wanted and build a positive reputation with ISPs. Monitoring deliverability metrics, such as opens, clicks, and bounce rates, and utilizing tools like Google Postmaster Tools and Microsoft SNDS is essential to adjust the warm-up strategy based on ISP feedback. Pre-emptive communication with mailbox providers, like Microsoft, may also be beneficial. Since the IP has no recent history, the process should be treated as a fresh start.