I'd Love Your Guys's Help With My First Build w/ Aftermarket Parts. Please Help Me.

Hey gang. I really don't know much about assembling an airsoft pistol but I'd really like to make a custom build for myself. I have been saving up and I've managed to gather a sum of money that I'd be comfortable spending to make my dream airsoft pistol.

I'd like to make a completely rainbow or iridescent build. I really don't know much about anything so I am asking for any help with where to start. I've heard that Tokyo Marui pistols have a lot of parts to choose from on the market so I think i'll go with the 5.1 Capa pistol from TM.

So far the only piece I've ordered is this rainbow slide. Is this the right one?

https://shopmnairsoft.com/products/mna-mirage%E2%84%A2-cnc-aluminum-slide-for-tokyo-marui-spec-hi-capa-5-1-1911?variant=43575284727957

Please help me find cool rainbow parts that are reliable and look really cool. Thanks for any help in advance.