Grammar fix
psych yourself up
prepare mentally
to mentally prepare and motivate yourself for something difficult or nerve-wracking
phrasal verbB2common
Hear it in context
Notice where the phrase sounds natural.
I had to really psych myself up to make that phone call.
Give me a minute, I'm psyching myself up to jump in.
Fix the pattern
One small grammar move makes it sound right.
Spelling it 'psyche up'; the verb form is 'psych'.