What a question.
Listen to some music, (the variety is endless and you will certainly find something to match your mood).
Read a book, (between covers is even better than a Kindle....) - the universe and its wonders can be found in pages; go for a walk; watch a movie; hang out with some buddies; have coffee with a friend; sip a beer in a city centre, and watch life go by (a wonderful way to chill in parts of Europe in summer); browse the internet; ask questions of your mind; seek answers to the pressing queries life throws at us........
Boredom - and to admit to boredom - is a strange one. Over my life, I have been frustrated, depressed, absorbed, transfixed, ecstatic, amazed, besotted, focussed, fascinated.....however, I cannot ever recall having been bored in my entire life.