So, you’ve decided to test IM and you’re in stage 1 testing. That means you’re haphazardly getting some intentions to manifest and others to not. Even stuff which should be simple and easy and you have no resistance to (such liking to see a blue feather today) isn’t working, and you feel frustrated.
That frustration is a sign of some resistance. As I’ve said elsewhere, the ideal state for manifesting (and, indeed, life) is a free and easy, flowing state where you simply accept what comes at you and just be happy or at peace. Its a feeling of Hanging On Lightly.
So, the reason might be that you’re too attached to the outcome of IM working or not, and thus you might see every single intention as a test of whether IM works or not, and your worries might be contaminating your intentions and your manifestations. In this case, its important to remember that one single intention proves little (unless it is a really big or specially meaningful one), and that you want to try out a whole bunch of intentions. Try to keep your critical mind out of it until you have more data. And I would suggest keeping track of your intentions, especially if you do some sort of formal meditation or visualization session. Just write what you intended for down, which will have the doubly benefit of increasing the likelihood that it will manifest (because writing things down is a great way to intend), and it will keep you accountable to see how well this model of reality has been working by counting both the hits and the misses.
So, take the long view. Instead of feeling that if you can’t intend a cab in the next minute, IM has failed, feel that this one intention is in a series of tests that you’ll be doing, so its ok if this one fails. And its ok if IM turns out to be incorrect, because then you’ll just move onto the next thing that might work. The important thing is you tried something most people wouldn’t come near.