Step 1 — locate the fixed sources first
Start with what doesn't move: a Wi-Fi router, a smart utility meter on the other side of the headboard wall, a cordless-phone base station. These are worth noting because, unlike a phone, they transmit on a fixed schedule regardless of what you do at bedtime.
Step 2 — check what's on or near the bed itself
A charging phone, a tablet left plugged in, an electric blanket or heating pad, extension cords running under the mattress. This is the highest-leverage category because it's also the closest — and usually the easiest to change.
Step 3 — note what's genuinely low-priority
A TV or monitor that's off, a battery-powered alarm clock, most furniture and bedding — items with no active transmission don't need to be on this list, and treating everything in the room as equally worth investigating is what turns a reasonable checklist into an exhausting one.
Step 4 — use the interactive version
This walkthrough is also built as an interactive checklist that gives you a tailored, no-cost suggestion for each item you check — faster than working through the list manually, and it doubles as a record of what you've already addressed.