Do push-ups regularly
Do chin-ups or pull-ups if you have a bar
Do bicep curls with dumbbells
Do hammer curls with dumbbells
Do resistance band curls
Do towel curls against your foot for bodyweight resistance
Use water bottles or backpacks as weights if needed
Train biceps 2 to 3 times per week
Do 3 to 4 sets per exercise
Do 8 to 15 reps per set
Increase weight or reps over time
Keep your elbows close to your sides during curls
Lower the weight slowly
Eat enough protein
Get enough sleep
Stay consistent