Domestic users registering for overseas AI tools, start by preparing these four things.

1. Overseas phone number
Used for registration, verification, and account recovery.
Short-term SMS verification and long-term number retention are not the same thing; beginners need to distinguish.
2. Stable email
Email is an asset of your account; do not casually use disposable emails.
Later, it will be relied on for recovery, notifications, and risk control verification.
3. Available payment methods
Many tools are not difficult to register for, but subscription and renewal are challenging.
Unstable payments can easily break the tool chain.
4. API / relay backup solutions
If you are doing automation, content matrices, or tool calls, relying solely on the web version is not enough.
At least know how to choose official APIs and relay stations.
Once these four are ready, then discuss Codex, Claude Code, Seedance, and Agent workflows.
Don’t reverse the order.