Hi _______ (friend),In working towards a still mind, the most important aspect is to disregard all of these naturally occurring thoughts.
Learn to only watch your thoughts, that's where the training begins.
Some schools would analyze these random thoughts, that is not what you're looking for now.
Do not latch on to any idea that comes up, do not give any the time of day. Not any musical thought, any lottery number, any ideas for dinner.
Let the thought come and do not answer, let it go for this practice. Good ideas will come during these practices, but don't engage; That's another practice, which is fine in its time. There is as much power in learning to let your thoughts go as there is in the brief periods where nothing is happening.
Yes, it is usually good to have an anchor to return to: such as breathing, or repeating casually and silently a non-meaningful sound “while not watching the breath”. Such a sound is "I am" or "I'm" which is really an American interpretation of the sound of a powerful but originally a “meaningless (doesn’t draw out individuality)” Sanskrit seed mantra. Do not choose any word, which changes the neutrality that a breathing anchor could offer.
Do not use any mantra if it moves in any direction except a change in sound. It should never be: "I am"..I'm here...I'm unique...I’ll show them….etc.It should never turn into a prayer or motivational self-talk, those are great but different.
A still mind can retool and retime your system, but the quest cannot contain a personal agenda.
Enjoy the sun
PS I break all my rules, but still try.