The 4-7-8 breathing technique based on pranayama is one of the best ways to relax and induce sleep when you are feeling antsy in bed. It helps a lot for my anxiety, particularly because I experience physical symptoms like restlessness or a racing heartbeat that don't help me rest. It also distracts me from overthinking.
Once you are tucked into bed, breathe out, then breathe in through your nose for four counts, hold the breath for seven counts and exhale very slowly through your mouth for eight counts. Repeat four times.
Drawing by Ruby Etc.