There are multiple ways how to sense if a deity is calling. A strange, unexpected, sometimes sudden drawn towards them that wasn't there before. You may see their name or shape pop up more often than usual, a rising curiosity towards without conscious focus on them. Drams, visions, or their symbolic animal appearing often than before (in these case always worth to double check how common these animals are or how often you encountered them before, just to keep it healthy and grounding).
ㅤIt is possible to observe how you feel when you hear their name, think about them or read about them; you may feel a bewitching, 'drawing in' sensation rising. If that's the case, there is definitely an undercurrent steaming behind the veil.
I think working with a deity often begins before you directly make a contact. This is the phase where you focus on the entity, think of them, read of them, listen experiences, stories, documents of them, gather images, artworks, and allow your consciousness and psyché to welcome their frequency. This is a good beginning of a tuning in.
ㅤYou can give them some offerings in the meantime, meditate 'on them' for balance and connection, and so on. They are more than aware of your intent when you open up, so once you feel like you are ready, you can step forward and invite them.
Being rejected is completely natural and more common than you imagine. Again, that's because they see through you, and they know exactly what they want. They have every right to say 'no' to working with a person, same way you can say no to them if they reach out to you. Lack of response, activity, stimulation or results in your practice are good signs of you being ignored.
Worth to mention, sometimes these are not signs of rejection, but your lack of practice or even a test, to see how you handle a situation in which you need to go further than you ever did. This is something only you should truly explore, and not let others tell you what's the matter.
And yeah, working with elements as a beginner is completely okay too.
