Hi @Rosemarie!
Here’s some useful information regarding your question:
The main difference between an amulet and a talisman is its purpose. A Talisman is used to attract or manifest a goal, which could be anything (for example, love, money, good luck, etc). 
Meanwhile, an Amulet is a bit more specific, an amulet is for Protection. 
So an amulet is basically a Talisman for Protection (here’s how to make one).
I say this because the best lunar phase is going to depend on what your intention or purpose is for this amulet/talisman. I recommend you to follow this guide:
In short, if the purpose is to boost, builds up, attract or heal, it’s best to do it during the Waxing phase (the moon is growing).
The Waning phase (when the moon is disappearing) is recommended to blow away any obstacles that get in your way, be they people or circumstances. It’s about banishing energies, getting rid of bad habits, etc.
The New Moon is great for new beginnings or fresh starts, and the Full Moon is about realization, fulfillment, dreaming big!
≫───•◦❈◦ ◦❈◦•───≪
Having said that, not all witches take into account the moon phase when they cast spells. Tonight there’s a New Moon 
so if you feel that is a good sign, go ahead!