1. Go to the promotion page (in French).
2. Press the green button for a free subscription.
3. Enter your details: first name, last name, email address, country and zip code.
4. Confirm your free subscription.
5. Copy the received license code.
Heimdal Thor Premium Home has free trial version on 1 month. Sometimes you can buy 1 year license key cheaper by looking for a discounts. Really rare there's some chance on free giveaway like it was 15 months ago.