My lords and ladies (of any gender), prithee, are you wondering what to wear to the mediaeval and renaissance ball? Fear not. Any attempt at period attire will be admired, and can be great fun, but is not required. There are many easy ways to dress oneself in something apt. See, for example:

Mediaeval costume in under 4 minutes: https://www.youtube.com/watch?v=XaH6v70h3ys
https://costumes.lovetoknow.com/How_to_Make_Easy_Medieval_Costumes
https://www.facebook.com/Medieval-Mask-Making-1676533352676701/
https://www.youtube.com/watch?v=botZOEBoLDQ (very easy guide to a dark ages cloak)
https://www.youtube.com/watch?v=ykhqMydeSdA (how to make a basic renaissance outfit)
https://www.tiktok.com/@mossy_socks/video/7244563917064752426
Renaissance costumes with things you already have (at 5m50s they say corsets and stays can be replaced by a vest so don’t put off by all the handmade stuff):  https://www.youtube.com/watch?v=avXgeM8ZATs
Renaissance (Ren) Fair outfits using everyday clothes: https://www.youtube.com/watch?v=utnK5tuyLzA

   

Of course, there are diverse merchants who will, for a small fee, attire one.

For masks, party shops, fabric shops, markets and the like have many options. You can also hire them, and there are many ways to make your own. E.g., see
https://www.youtube.com/watch?v=bKJbxr75quM
https://www.ehow.com/how_6399582_make-paper-mache-masks-face.html
https://www.wikihow.com/Make-a-Masquerade-Mask
https://feltmagnet.com/crafts/How-to-make-a-plague-doctors-mask-Black-death-dead-diseased-middle-ages-Tudor-times
https://www.youtube.com/watch?v=p6evWdJeIbU
https://www.fleecefun.com/how-to-make-a-knight-helmet-free-template-file/
https://www.fantasycostumes.com/cosplay-guide/dread-pirate-roberts/

Satinwood Creations makes beautiful hand-made leather masks. Contact 0428 396 995 or satinwoodcreations@outlook.com.au

There are many other online resources for dressing up in period outfits. Search for something like “easy medieval outfit” or “make renaissance costume”.

Of course, feel free to come in any attire you like, but if you do make an effort on a period outfit, it will be admired, and many people do. It all adds to the fun.