I designed a template to allign my MagSafe ring on the Galaxy S24 Ultra. It is intended so not disturb the wireless charging which is the case with most of the available cases as they have the magnets positioned way to low.

I used the magnetic Ring by SYNCWIRE which works perfectly fine for me.

https://www.amazon.de/Kompatibel-Magnetisches-Drahtloses-Aktualisiert-Magnetischer/dp/B0CQTHX3JR/ref=sr_1_4?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91&crid=2K9FKG50R568E&dib=eyJ2IjoiMSJ9.cNRCInBtzC2jX-Yqv10SUJAd-lq3ggZt-98kC1ZzbZ8AWr8bqbXLYfFPPUANX_jKJbC6l8QAGjSUB6bidgmuL4nyNNHMeDdNbLC3scaTcA_bz2bOBikS7jY7LSKGMhGQztCJ7HaDSzhXrq4l4uVilgkdSK2aQ3IDgjVUezdXDBTPzsxBGjAuclV8g2ZwdMzoHkD6bA83ZEpNEE4qtJHzzkfcohqHe7J8j9Z0w7qCne4.UI88kYUu1Vn1f8LG-iLfyHal0p_wkQUtAE4E5ea3Yyk&dib_tag=se&keywords=syncwire+magsafe+ring&qid=1717263643&sprefix=syncwire+magsafe+ring%2Caps%2C225&sr=8-4

The diameter of the ring used must not exceed 57mm.