Getting into Eaglercraft takes about 30 seconds: open the URL, wait for the client to load, and you are in. But a few setup steps will make your experience significantly better.
Adjust your render distance first. The default setting works on most machines, but if you experience lag, dropping it by two or three chunks usually solves the problem without noticeably affecting visibility. Eaglercraft runs in a browser, so it has less memory headroom than the native client.
Rebind your keys if the defaults feel awkward. Eaglercraft supports full key remapping through the settings menu, and matching your bindings to whatever you use in regular Minecraft eliminates the adjustment period.
For multiplayer, look for servers with active player counts between 10 and 50. Smaller servers tend to have friendlier communities and less lag, while very large servers can feel chaotic and may have performance issues in Eaglercraft due to browser limitations.
In survival mode, the first-day priorities are identical to standard Minecraft: punch trees, craft a workbench, make wooden tools, find or build shelter before nightfall. The mob AI in Eaglercraft matches the 1.8.8 behavior, so zombies and skeletons are aggressive but predictable.
If you plan to build large structures, switch to creative mode on a singleplayer world first. The browser can handle complex builds, but testing your design in creative before committing resources in survival saves time and frustration. Eaglercraft supports world saves through your browser, so your progress persists between sessions.