There’s nothing sinful or wrong about making plans. It’s a wise thing to make plans. What is problematic is when our plans don’t take into account God’s Word or His will for our lives.
When we make plans, we need to do so prayerfully so that our plans don’t contradict God’s Word explicitly and implicitly oppose His will for our lives. When we humble ourselves before God, we can trust the Holy Spirit to speak to us, in our prayers or through godly counsel of fellow Christians.
If we make plans without acknowledging that the LORD our God is in charge, we can get very disappointed when our plans fail, and even worse, we can get angry at God and suffer even more as a result.
So, make plans wisely, but remember, God’s will before our plans, always.