Beginner Shadow Priest tips for Solo Shuffle?

Hey everyone,

I'm completely new to Shadow Priest and looking to get into Solo Shuffle. I've never played SP before, so I’m trying to wrap my head around the basics — especially for PvP.

I have arcane mage on 1,8k, resto druid on 1,8k and mistweaver on 1,8k and next one I'd like it to be shadow priest

A few questions I have:

• Is it better to use Mind Flay or Mind Spike in PvP?
• When should I be casting each one?
• Any must-know tips or priority rules for someone just starting out?
• What talents or builds work well for solo shuffle?
• Any general tips on positioning, burst windows, or surviving as SP?

Would love any advice or beginner-friendly guidance. Thanks in advance!