"Clocking waveform" implies logic. Logic signals, unless slew rate limited, generally have fairly fast edges, and a cheapo clips to BNC cable into a 1 Meg scope input will give you horrible reflections and ringing on those edges, which will make reliable triggering difficult.
One workaround if your signal is capable of driving a 1K load, is to terminate the scope end with 50 ohms (either internally if it has that option, or with a BNC T (m-m to f) with a 50 ohm terminator on the other arm of it), and add a 1K resistor in series with the signal, at the clip. That gives you 21:1 attenuation, but with a reasonably flat response and no reflections. Even better is to use a 950 ohm resistor for 20:1 attenuation.
Ground clip lead length is still problematic for ringing - shorten it if nessercery!