Make this really easy for the guys:

  1. Position yourself within smooching range. 30-40cm is best. This must be done in a "suave" manner, ie, don't make it totally obvious that you're lining up for a kiss.
  2. Stare into her eyes. This must be done under the guise of "making eye contact" during the conversation.
  3. Conversation lulls, non-awkwardly. Usually safest to let her have the last word.
  4. Count to five. Slowly. A faint smile and slightly more opened eyes on your part helps to prepare her.
  5. If you're still silent, incline your head minimally towards hers. Inclination change should be no more than 5 degrees or 2 cm, whichever is smaller.
  6. If she wants to smooch, she'll catch the signal and respond in like manner. Bonus points if she closes her eyes as she goes in for the lip-lock. This indicates a willingness to trust you. Don't mess it up.
  7. Slowly bring faces together, tilted properly so that noses don't collide (which can be disastrous in the "trust" department). Keep your eyes open long enough to properly align your lips with hers (since her eyes will probably be closed already). After lips are initially positioned and in contact, close eyes. Experimentation with further action is left as an exercise for the reader.

This process has worked successfully (executing desired smooches as well as avoiding undesired smooches) several times for me.