Question 1: What is the first thing that I should ask myself even before I think about God and spiritual life?
Answer 1a: "Enquire whether you really want liberation or whether you are simply talking of higher things out of curiosity...", Swami Sivananda (pg. 269, Science of Yoga, vol. 6).
Answer 1b: "Do you want God?... Do not cheat yourself: be straightforward," Swami Sivananda (pg. 413, Sadhana)
Question 2: What is the next most important thing that I should do about my determination to continue in spiritual life?
Answer 2: "Even if Lord Krishna remains with you, he cannot do anything for you unless you are fit to receive him and his teachings. Realise this point well and purify yourself thoroughly by means of... Japa, brahmacharya and control of the senses," Swami Sivananda (pg. 265, Science of Yoga, Vol. 6)
Question 3: I am serious but I don't have the time.
Answer 3 a: "Plod on in your sadhana. Give up idle talk, tall talk, gossip and backbiting. Save your time," Swami Sivananda (pg 169, Science of Yoga, Vol. 6)
Answer 3 b:"We must minimize all unnecessary waste of time in futile thinking, gossiping, aimless activities, wandering, etc. Then, we will get plenty of time for our spiritual practice." (pg. 341, meditation and spiritual practice by Swami Yatiswarananda)