The problem becomes more imminent with small displays, e.g. when you work on a 13″ MacBook Pro without external display. Usually you have to find an application which only has a few menus and hope that you can access the necessary program icon.
That is where Bartender comes into play, which is not available at Mac’s AppStore but can be downloaded and licensed on the website for $15.
Bartender, Mac Menu Bar Item Control
Bartender adds a second menu bar right below the regular one which you can place manually wherever you want. This second menu bar is the container for all icons you do not want to show up in your Mac’s menu bar. Each single icon can be individually configured. For each icon you can decide if you want to leave it as is, move it to Bartender’s menu bar and whether it should show up in the regular menu bar for a few seconds on change. This means, that e.g. the Dropbox icon will show up when the Dropbox sync is in progress. Afterwards, the icon will vanish into the Bartender bar once again.