One can turn away from worthless and useless things if one acts in order to gain the good pleasure of Allah alone. Believers know that they need to use the time granted to them in this world in the most efficient way because what they do in the world determines their permanent abode. Therefore, in every deed they perform, they aim to gain a good deed for the Hereafter. Naturally they talk, have fun, eat, laugh, think and work just as everyone else does; but in doing these things they always have good intentions which are likely to be of benefit to other people and to the religion.
Apart from these things, all believers' acts serve a purpose. They always turn towards good deeds that will gain them Allah's approval the most. For example, anyone can talk about automobiles. Yet a believer would not spend hours in such conversation while there are other urgent things to do. Likewise, a believer would not chat for a long time about which team will be the winner in a football match when talking to someone to whom he can communicate the religion of Allah. That is because the crucial thing at that moment would be to enlighten that person about the existence and the greatness of Allah, and about what he has to do in order to deserve Paradise and to avoid Hell.
In brief, believers neither plunge into long discussions on topics that are not relevant to the benefit of the religion and of Muslims, nor spend more than a sufficient and reasonable time on these subjects. They use their time efficiently by properly distinguishing between all worldly matters. They do this by use of their conscience and reason. They decide what is "worthless" and what is useful, and do not compromise this. The attitude adopted by believers when they hear "worthless talk" is related in the Qur'an in these words:
When they hear worthless talk they turn away from it and say, "We have our actions and you have your actions. Peace be upon you. We do not desire the company of the ignorant." (Surat al-Qasas: 55)