Click on the "Instruments" icon on the left-hand side of the screen. Load any drum instrument plug-in you have. Ableton comes standard with the Impulse drum machine.
Double-click on the name of the plug-in you chose to load a fresh, blank instrument. You also can click on the drop-down arrow and choose from a bank of preset kits. Drag the instrument to its own MIDI track in the workspace.
Browse your sample folder for the samples that you want. You can access this folder by clicking on the icon on the left side of the screen.
Click on various samples, such as kicks, snares and cymbals, to preview their sounds. When you find ones you like, drag each to one of the eight sample squares in the Impulse machine. You can do this even if you loaded a preset kit and want to exchange a single instrument.
Press the record button on the Impulse's MIDI track to hear the samples from the machine itself every time you trigger them. You can trigger the samples by using a MIDI controller, which is the preferred way to trigger sounds among musicians, or by using your computer keyboard or mouse.
Repeat the process to create a second drum kit if you need more than eight samples for the Impulse. Other drum plug-ins may have more slots. You also can rewire other programs, such as Reason, to Ableton and use their samples and instruments.