When learning a new word is it important to learn all 12 forms(6cases for singular and plural) as well as the changing placement of stress in the word? Or should I just learn the nominative and my mind will start to fill in the gaps overtime? I need suggestions. I regularly try to be thorough in my studying, however I think in the end I end up not communicating as I should.
If your goal is communication, it is not so important to learn all 12 forms just like in English it is not necessary to learn all the 12 tenses to communicate effectively. It's more important to listen as much as you can to as many sources as possible - TV, movies, live conversation, radio, podcasts. Take notes, hit replay, and repeat what you hear (check out Эхо Москвы- you can listen to podcasts in slow motion and follow along with a transcription of interviews/talk shows). Do this for an hour or two every day. You will learn that certain verbs are used in certain contexts, you will hear idiomatic expressions, and you will begin to understand the use of verb aspect. After a while, instead of thinking which case you should use before you speak it will come out naturally as you will have heard it spoken before.
The main obstacles to communicating with verbs in Russian are verb aspect and verbal prefixes. That said, you should be definitely be aware of the basics: the different types of verbs (regular and irregular), how they are declined, the main verbal prefixes and verb aspects - perfective and imperfective. Learning verb aspects cannot be stressed enough because they indicate if an action was completed successfully or is ongoing (я иду vs. я ходил / сходил / пошёл ). To do this in English we use auxiliary verbs like “had” and “have”. I would suggest learning the perfective and imperfective forms of new verbs. Finally, don't get too discouraged when you start to learn Russian verbs of motion. This takes a while to get used to and you will gradually understand with time and practice.
For your reference, one of the best textbooks I have come across is Using Russian, A Guide to Contemporary Usage
My suggestion would be to learn the basic, nominative form, then take the cases one at a time, learning the endings (and contexts) for each as you go. Every book I've seen takes this approach and I can't imagine doing it differently.
I don't know what stage you're at in your Russian, but if you're working on your own, my enthusiastic recommendation goes to Nicholas Brown's 'New Penguin Russian Course' - it's pretty inexpensive on Amazon, has an answer key, and gives the information you need at each step without overwhelming you. Its only real drawback is the lack of audio, you'll need to find that elsewhere.
Listening to Эхо Москвы etc is great but if you're just starting out, don't let it discourage you - most of my students found it challenging even after 200 hours of classroom instruction. But finding music you like is a great way to tune your ear to the sounds and rhythm of the language. Успеха!