To create a list of 100 contacts, please go to contacts, click on the first contact to select, then click on custom and enter 100 in the box provided and it will select 100 contacts automatiically. After that, click on bulk action and select "Add to Static list" and select a list from the drop down and enter a tag like "first100" to identify them.
 
Note: You can enter the number in the box provided to select those many contacts. 
 
 
To select the next 100 contacts, please apply a filter "Tag is not first100" and it will list all the contacts excluding those 100 that were already added to the list. Click on the first contact, then click on custom and enter 100 in the box provided to select 100 contacts. After that click on bulk action and select "Add to Static list" and select a list from the drop down and enter a tag like "second100" to identify those contacts.
 
Note: If a list is not created already, please select "Add New" and create a list.
 
Please repeat the same if you want to create more number of lists. 
 
Please check the video: