You need a couple of things:

1) Suction cup.

2) Screwdriver kit that contains pentalobe and torx bits. You don't need to buy some expensive kit as you can get them cheaply from any hardware store.

What is the suction cup for?

Pulling off the bottom plate once you've removed the screws. It's not essential, but it obviates the risk of damaging the case with a spudger or other prying tool.

I always lifted it up from the heatsink side with my fingers. It overhangs a few mm from the hinge.

I think it's not possible to open 2016+ models without suction cup anymore, there is some weird clips inside that open up with bending of of case.

I think Apple finally won with making their computers impossible to open.

Ifixit has a lot of good tutorials with Images you can check them out.

You can Google that and find many guides on that topic. iFixit has really good guides.

TLDR: Remove the screws on the bottom. You need a special screwdriver and keep in mind that (at least on the <=2015 models afaik) there are different size screws used around the hinge.

You probably won't find that screwdriver at local hardware store though. I had endless issues finding even semi-common torx bits at Lowe's.

ifixit can solve that problem as well (though reasonably expensiveish (additional thing. their magnetic mat with squares on them was the greatest purchase I ever made for the workshop at my first job.))

The ifixit Pro toolkit really is a necessity for anyone even remotely interested in taking things apart.

I've used mine to take apart every conceivable consumer electronic, and through social bits for Nintendo, Apple, etc are priceless.

I also got the magnetic mat, a Christmas gift from my wife, and when disassembling things with lots of screws is useful for drawing out the device for their location.

> You need a special screwdriver

P5 Pentalobe screwdriver: https://en.wikipedia.org/wiki/Pentalobe_security_screw