1 easy mistake to make is to ignore the rotation, and pigeon hole oneself into a particular stock/sector.
stuff goes in/out of favor - unless you just buy total global index and forget about it.. but i think paying attention to the rotation probably brings extra 2-3% return, which is significant over long term.
I used to monitor 1-2 dozen country/region ETFs, have since added a dozen or so index leaders, (borrowing a page from FreeTrader's book).
following these everyday, it doesn't take a rocket scientist to see the rotation.
then the play is not hard.... when the broad market retreats, absort the stronger sectors, when the broad market goes high, get rid of the weaker sector holdings.
when is low, when is high? it's not exact science... I'd say the lows are quite easy to identify, VIX spike, media doom and gloom, retest of previous low etc.. the highs are not easy to identify, need to take some chances.
just go around the block a few times, it will gradually feel like riding a bicycle.