Reading and meditation are important before you begin to design your altar and your devotional rituals. Both are necessary and will give yo uthe basics of symbolism for setting your altar, and the names and some of the titles by which your chosen deities should be addressed. Your work will reveal tales and materal which can become the basis for the words of your devotional rites, as well as the conditions and situations in which each deity is most often encountered. A devotional can of course be done with no props other than your intent, particularly when very little is known about a deity. But using linking symbols, if they are available, is always helpful.
Preparation is no guarantee of instant success, but neither is sincerity alone.
Time and effort are both important ingredients for your devotional work. The nature of spiritual work and development is slow and painstaking. Success will undoubtedly come, but you must reach for it and put your best effort into your workings. Always remember that what you get out of your devotional rituals will be dependent upon what you put into them. Your effort may be great, but your rewards will be greater.