Three of them, all under Settings, Display and Sounds. Video Resolution should be set to what your television actually accepts rather than left on automatic, because a stick negotiating a mode every time a stream starts produces a black gap that looks like a buffering fault. Match Original Frame Rate matters for live content, since sport shot at one frame rate played back at another produces the judder people blame on their connection. Audio passthrough is the third: leaving it on when the television cannot decode the format gives you picture with silence on some channels and sound on others. Set these once and a whole class of apparent stream problems disappears before you have installed anything.

Wired wins whenever it is practical, and a USB Ethernet adapter is inexpensive. If you stay wireless, get on the 5 GHz band rather than 2.4 GHz, which is crowded in most neighborhoods and is the usual reason a stick that tests fine at midday falls apart at eight in the evening. Do the arithmetic for the household rather than for one stream: 15-25 Mbps for each 4K stream, 5-8 Mbps for each 1080p one, running at the same time as everything else in the house. Two 4K streams and a video call is a real load on a modest line, and no app setting rescues a connection that is genuinely full.

More than the app size, because the APK, the installed app, its cache and the guide data all share one small partition. Look under Settings, My Fire TV, About, Storage before you begin. If the stick is close to full, remove games and unused apps first, then clear caches on the big ones. The guide file for a large catalog is the item people forget: tens of thousands of channels carry a proportionally large program listing, and a stick that cannot cache it will refetch it constantly. Deleting the APK after install returns a chunk of space immediately, and Downloader offers to do it for you at the end.

Order matters because each step makes the next one either easy or impossible to diagnose. Do the network first, then the display, then the storage, then permissions, then the app, then the credentials, then the channel list trim. If you install the player first and something misbehaves, you have no way to tell whether the app, the band, the display negotiation or the storage caused it. Doing it in sequence means the only variable left by the time you enter credentials is the service itself, which is exactly the variable you want to be testing.

1. 1Network: 5 GHz or wired, checked at the busy hour, not at noon
2. 2Display: fixed resolution, frame rate matching on, audio format confirmed
3. 3Storage: headroom cleared before the download starts
4. 4Permissions: Install Unknown Apps granted to Downloader only
5. 5Credentials last, so the service is the only untested variable

Three fields. A server address including its port, a username and a password, which arrive here about five minutes after checkout. Enter them once in whichever player you installed, pick the Xtream Codes method if the app offers it, and let the channel list and the guide populate before you judge anything. Then trim the catalog: players keep the whole visible list in memory and get unstable somewhere above roughly 18,000 channels, so hiding groups you will never open is a stability step rather than a cosmetic one. Installs are unlimited across your devices, so repeat this on every stick in the house; only concurrent streams are capped, at 1 to 5 by plan.