From AWS Console, select Services, EC2 and then Load Balancers
Click Create Load Balancer button and Application Load Balancer as indicated below:
In the 1. Configure Load Balancer step, enter the load balancer Name (e.g. unicorn-lb), choose the VPC that you use (e.g TargetVPC) and select your public subnets for at least two subnets (public-a, public-b) as below:
In the 3. Configure Security Group settings step, choose the LB-SG security group.
In the 4. Configure Routing step, select New target group in the Target group and provide a name for the target group (e.g. unicorn-tg). For the Target type, select IP, leave the default for the other fields and click Next: Register Targets
Leave the default of register targets, click Next: Review and then click Create to create the load balancer.