if you have a volt meter, check each cell’s voltage after you charge. And leave room for a bit of drift, charge to like 4.1v per cell.
Check religiously the first time you charge pretty frequently in case you have faults.
Check a few times during charge the next few times.
If it’s behaving consistently, you can gradually wean off to maybe checking once every 10 charges.
If you see cells drifting a lot, fix your pack.
If drifting a little, you can use it until it doesn’t feel safe then wait for your balance leads and balance charge.
Also check voltages if you’re close to empty. if you’re out of balance at the bottom you can cook a cell.
This is diy so everyone must set their own safety tolerance. Don’t do above if you’re not comfortable with elecricity.