Tickera is an online event ticketing system intended to be used for selling tickets on your website and delivering them to the customers as download links via email. That said, the only way for the tickets to get created in Tickera is to add them to the cart and successfully finish the checkout process. So, if you want to create tickets manually, you would need to follow that exact same path. Now, to avoid the actual payment on the checkout, you can create and use 100% discount code (known only to you).
Apart from this, if you are running Tickera accompanied by WooCommerce via our Bridge for WooCommerce add-on, you can install and use WooCommerce POS plugin (free version of it can be found here) which will allow you to create orders in POS-like environment in couple of clicks. However, the downsides of this is that you cannot collect attendee information (be it the default first and last name fields or the ones you have created with Custom Forms add-on) and even you will be able to create the ticket this way, you will still need to navigate to Attendees & Tickets area of Tickera and view or download the ticket from there (you can have two browser windows open at the same time; one with POS environment and one with Attendees & Tickets area). Also, this approach cannot be applied if you're using Seating Charts add-on given that this POS plugin cannot load seat maps created with Seating Charts add-on and therefore any ticket purchased through POS plugin will not have assigned seating.
Important: if you are using Tickera with WooCommerce via Bridge for WooCommerce, you might notice that WooCommerce allows creating orders manually. However, if you try to manually create an order with the tickets as WooCommerce products, this will NOT result in creating tickets. Order will be created successfully but the tickets won't be created.