This Ableton tutorial covers two quick pre-recording settings that make MIDI capture cleaner and more consistent. Before hitting record, set Record Quantization to sixteenth notes via the Edit menu, and configure the metronome to count in for one bar with a Wood click sound.
The key setting here is "Enable Only While Recording," which makes the metronome switch on and off automatically whenever recording is toggled, so you never have to manage the click manually between takes.