Please avoid T-Shirts & anything with zips, buttons or pockets as these are all dangerous to your training partners.
For MMA kit beginner students will first need their own Boxing gloves & Shinpads. Next they need mouthguard and groinguard - and then their own 8oz sparring style MMA gloves (not 4oz pro style). Then they will most likely want to get some comfortable focus pads and nice Thai-pads...
For clothing beginners need undershorts and shorts (without zips, buttons or pockets), and a rashguard-style tight fitting top. Women will mostly also want a comfortable sports bra under their rashguard top.
For some more info on these items see below:-
Boxing gloves: For most adults 14oz is ideal - but if you're less than 60kgs or have small hands then 12oz might be better!
Buy Here: RDX Boxing Gloves
Buy Here: RDX GroinGuard
Mouthpiece: Critical for protecting your teeth while competing and training.
Buy Here: Opro MouthGuard
MMA gloves: Necessary for competitions. You should wear MMA gloves during sparring and grappling sessions as well so you can get accustomed to them.
Buy Here: RDX MMA Gloves
MMA shin guards: Sock-style are faster to put on and better for MMA rounds, but the Straps-style are more robust and better for pure kickboxing rounds and harder kicking.
Buy Here: Fumestu Sockstyle, RDX T1 Shin pads
Thai pads and focus mitts: For using with a partner to work on punches, kicks, and other strikes.
MMA Clothing / Uniform:
Rashguard top Buy Here: UnderArmour Rashguard
Undershorts Buy Here: UnderArmour Undershorts
Shorts (No Pockets!) Buy Here: Blitz Shorts
Spats are also an option :-