I think this is the hard part...where you're starting to panic and wonder exactly what you've gotten yourself into and why you thought this was a good idea and what if you can't do it and what if a three-legged elephant crashes through your garden wall and stomps your deck into oblivion. It will get easier as time goes by; you'll start to create a bond with your chosen deck and it will begin to open up to you, and all the reasons for doing this IDS will become more clear and worthwhile.
In the beginning, I was horribly panicked about whether or not I'd chosen the right deck, and whether or not I could handle the time-frame I'd given myself, but once I stopped THINKING and started FEELING, it all seemed to make sense in my mind.
I've been working exclusively with my Bohemian Gothic for the past few days, simply getting to know it and letting it get to know me. There's been lots of just idle shuffling and meditating on specific cards and simply admiring the art and love and time that went into this deck, and I feel that already, the bond is beginning to form. The more time I spend with it, the less I'm tempted to reach for another deck.
I've realized that I often used the option of having multiple decks to use as a crutch; you know, "Oh, this deck isn't vibing me today, it gave me horrid cards, I'll just grab another deck and start over." I feel that being absolutely committed to one deck will make me a better reader in the long run, because it will force me to read the cards as they come, and not just push them aside and draw from a new deck.
I know that to some people, they're just pieces of paper with pretty pictures on them, but over time, I've begun to see my decks as living, breathing life forms that deserve respect and care and love, just like we do. Garbage in is garbage out, and it's my belief that if I put faith and trust in my abilities as a reader and in the strength of my chosen deck to tell me what I need to know, then I'll get the same back.