One tip I would like to share is try meditation. Any practice will suffice. The idea being to expand your awareness of your direct knowing, engaging and developing your primary awareness. That comes about for most of us when we quiet our attention to our physical or secondary attention.
Just saying no, is one way to do it, empty your mind; but usually sucks for most of us. I prefer to fix a question, more Zen like in approach. Set an open question, one that has no one answer... and hold on to it as if your life depended on it. Asking and then becoming aware of everything that comes up while you wait for an answer.
Do this for a minute, then write down everything you remember or tell it to a friend. Then do it again for two minutes. Increase by one minute, until you loose focus and start thinking of other things. Write that down too, but cut back on the time. You can stop for the day when you get to that time limit that you fell down on.
Day to day you may find your ability varies, so start lower than your last success each day.
It helps to do it in the same place, at the same time, every day. You can do it anywhere you won't be interrupted, interruptions count as things that come up when they happen.
If nothing comes up, congratulations! You are approaching nirvana, satori. You have stopped your internal dialogue... ;-) Seriously, how long can you hold onto this nothingness?
Whatever you do, do not seek the nothingness of mind by force. Blocking your thinking is a sure way to invite death. It is the discipline of silence you are cultivating. This may be more easily achieved with the intent to hear what is going on instead. And then to direct that hearing to a specific question. When you achieve silence in waiting for the response you have the proper way to quiet your mind without killing yourself.
Do this every day for a month. Review your journal and see what your next step will be.
Remember: unconditional means no judgment, no comparisons, acceptance and appreciation for everything that comes up. Love and thank yourself for the opportunity and the results it brings you.
Meditation has been proven to increase brain mass, influence physical events, and improve your health. Try it, you'll like it.