Formal:
* Много любви (Mnogo lyubvi) - This is the most literal translation, meaning "much love."
* С любовью (S lyubovyu) - This means "with love" and is often used in formal settings.
Informal:
* С любовью (S lyubovyu) - This is also used informally, but it can be seen as more formal than other options.
* Тебе много любви! (Tebe mnogo lyubvi!) - This means "Much love to you!"
* Много любви тебе! (Mnogo lyubvi tebe!) - This also means "Much love to you!"
Other options:
* С большой любовью (S bolshoy lyubovyu) - This means "with great love" and is a more heartfelt option.
* Целую тебя! (Tseluyu tebya!) - This literally means "I kiss you!" and is often used to express love and affection.
The best choice for you will depend on the specific situation and your relationship with the person you are talking to.