Adding IPs to your IP group is very easy.  First, go to "IP Addresses," select your IP group or create an IP Group by clicking "Add IP Group", if you do not have an IP group already.

Once you are in your IP group, click on "Add IP Addresses." You can add which IP group to exclude (excluding means that same subnets won't be selected), whether you wish to buy "Dedicated" or "Shared" IP address, choose IP's based on "class filter" as well. Click on "Next" once you've made your selections.

You can choose your IP location selection by clicking on the "+" next to the Country, choose the city, enter the total number of IP addresses you wish to buy under IP count, and if you wish to add more website slots to the IP address, you can do that as well.

If you are ready to place an order, click on "Place Order." Once your invoice is paid, IP addresses will be automatically allocated to your IP Group, and you can start using them.