Pick a co-founder (or “Other…” for anyone else), adjust the fields, pick static or animated, then copy. The animated version uses a GIF icon (12 KB) — the only animation email clients reliably play; everything else in the signature is plain, inline-styled HTML.
https://brand.hilo.cx/logo/ — upload
hilo-icon-animated.gif and hilo-icon.png (both in
marketing/logo/) to that location. The GIF opens with the finished mark, draws
the thread once, holds, and repeats — clients that freeze GIFs (old Outlook) show the
finished mark, never a blank.