What does that mean to walk after the Spirit?
Rom 8:1 There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit.
What does that mean to walk after the Spirit?
Let me use ‘leading the blind’ as an example. If I'm a blind man, how do I live my life? I need someone else who has eyes to take me by the hand and lead me through this world. Now, in this context, who’s the blind man? That's us: we're blind. We need the Spirit to be out in front of us leading us through life saying, do this and don't do that. And where do those instructions come from? It’s all in the Word of God, and more specifically, in Paul’s epistles. We just need to learn it and know it, and then yield your members unto that leading.
To be led by the Spirit is not complicated. Paul said the following in Corinthians,
1Cor.12:13 For by one Spirit are we all baptized into one body, whether we be Jews or Gentiles, whether we be bond or free; and have been all made to drink into one Spirit.