Get a case with a wrist strap;

Get a usb-charge only cable/adapter for when you want to charge it when out and about.

Get a usb-c to headphone adapter.

Play around with multi-profile alerts, and work profiles for separation.

Play around with file-scopes, and contact scopes.

All y'all downvoting recommendations: That's a really negative way to participate in a community. People are genuinely giving their earnest real lived recommendations (i haven't seen one meme recommendation in this thread) and some of you downvote them for it. We wouldn't have anything to talk about if we all thought exactly the same thing, and had the same opinions.

F-droid session installer, aurora store for google play apps, second profile or 3 for main non invasive apps, google apps, then tor privacy app usage on 3rd. Create backups of each on a flash drive use experimental app data feature in settings. Storage scopes for google app usages, deny most permissions in all profiles, use the camera and mic block toggles. Setup distress in the settings. Download wasted app on fdroid if you like it for extra precaution and settings. Use private messengers. FUTO makes good voice dictation, password storage bit warden its pretty seamless to use. Don't use fingerprint or face ID. Go through the settings and tweak as you need.

You don't need a lightweight launcher like KISS, but... Damn if KISS isn't just a good fucking launcher

Regarding profiles, having two is generally recommended - your main profile with no Google services, and a secondary profile only for apps that absolutely require Google Play Services. Personally, I just dump everything in one profile and deny nearly every permission to anything Google, and on top of the sandboxing that's enough of an improvement over stock Android that I don't bother with two profiles.

One thing I wish I knew going in, apps installed via Aurora store (google play store front end), for example ProtonMail typically rely on google play services to correctly send push notifications unfortunately.

You can remedy this with a seperate profile that can run in the background with google play services and apps that you want notifications for if you take issue with running google software running on your main profile.

Other than that, I've actually found GrapheneOS on my pixel 8 to be a much better software experience than my previous S22 without any tampering at all, both privacy (obviously) and functionally.

Congrats and enjoy your new freedome phone, you won't ever look back!

Check out FUTO.org's keyboard, best gboard alternative I've ever used.

The Aurora store is also a nice front end replacement for Play Store if you go the sandboxed Google services route.

Also, F-Droid Basic is out, which is just a newer F-Droid.

For an excellent Pixel launcher alternative, check out Lawnchair 14's Beta 2, or nightly from their github.

The suggestions people are making are good but I want to point out that GrapheneOS has good defaults so you don't need to do much except use your phone. If you don't have a particularly high threat model you shouldn't need to make any other considerations (beyond just what software you use on your phone, like if you use something like discord or whatever)

I will add on top of all the other recommendations, in F-Droid settings, turn off all anti-features. If after doing that, an app you are looking for is not available, check what anti-feature it has for why it's not listed.