すぐ, and especially 今すぐ, is my habitual way to express "soon", or "right after this".
I know that じき means more or less the same thing, and when I hear it or see it written, I get the general meaning of the sentence.
However, I don't feel comfortable saying it myself because I'm unclear on how they differ and what the nuances are.
What are the conditions in which to choose one over the other, and do they differ in meaning?
じき means temporally farther than すぐ. I don't know if the meaning of じき overlaps with the English soon. If it does, then soon has a broader meaning than すぐ. じき can instead be translated as 'sooner or later', or 'eventually'.
じき and すぐ are analogous.
じき（に）〈すぐに〉 in a moment； immediately； 〈間もなく〉 soon； in a short time； before long
e-g(1).もうじき12時だ. It is almost ［close on, getting on for］ twelve o’clock.
e-g(2).この子はじきに物を覚える. This boy learns very quickly ［is very quick to learn］.
〈直ちに〉 immediately； at once； straightaway； instantly； in a moment ［minute］； in no time； on the spot； right away ［off］
e-g(1).よろしければすぐおいでください。 Please come here soon if you don't mind.
e-g(2). 彼女はすぐ医者を呼ぼうと言った。 She proposed that a doctor should be called in immediately.
