Finish the mix before chasing loudness
Check that the kick, bass, melodies and percussion are balanced before placing a limiter on the master. If one element is too loud, correct it in the mix rather than forcing the entire track through heavier limiting.
Leave sensible headroom and avoid clipping the master output. There is no single peak value that guarantees quality; the important point is to provide a clean file without accidental distortion.
Listen for technical problems
Check the beginning and end for clicks, unwanted silence, abrupt cuts and reverb tails that end too early. Listen for harsh resonances, muddy low frequencies and distortion that was not intentional.
If the beat is intended for vocals, consider whether the midrange leaves enough room for a lead performance. A louder master is not necessarily a better instrumental for recording.
Export the correct file
Use the sample rate and bit depth requested by the mastering engineer, distributor or delivery specification. If no requirement is supplied, ask rather than guessing.
Keep an unprocessed mix export and the editable project. Give files clear names so the correct version can be identified without confusion.
Judge loudness in context
Streaming platforms may apply loudness normalisation, so maximising loudness at the expense of dynamics can be counterproductive. Aim for a clear, controlled sound that suits the style.
If you master your own work, take breaks and compare at matched loudness. If you hire an engineer, provide notes about the intended sound and avoid stacking multiple unneeded mastering chains.