The tool evtest-capture is currently only available in a git repository. To install it, do the following:

 $ git clone http://cgit.freedesktop.org/~whot/evtest
 $ cd evtest
 $ autoreconf -iv
 $ ./configure

Once the tool is installed, simply do the following:

1. run the tool
2. perform various touch actions (e.g., make some gestures on the target surface)

3. share the output with friends

 $ sudo ./evtest-capture 
Available devices:
/dev/input/event0:      Lid Switch
/dev/input/event1:      Sleep Button
/dev/input/event10:     N-Trig MultiTouch
/dev/input/event11:     N-Trig Touchscreen
/dev/input/event2:      Power Button
/dev/input/event3:      AT Translated Set 2 keyboard
/dev/input/event4:      Integrated Camera
/dev/input/event5:      ThinkPad Extra Buttons
/dev/input/event6:      SynPS/2 Synaptics TouchPad
/dev/input/event7:      Video Bus
/dev/input/event8:      TPPS/2 IBM TrackPoint
/dev/input/event9:      N-Trig Pen
Select the device event number [0-11]: 10
Writing to 'evtest-capture.xml'
Capturing device 'N-Trig MultiTouch'.
Press Ctrl+C to stop.

After hitting ^c, the capture will be available in evtest-capture.xml in the current directory, ready to be attached to a bug