Confusion on Mastery 6

So I finally got to Mastery Level 5 on Fiora last night and I'm not entirely sure I get how to get to Mastery Level 6.

From what I understand I'm supposed to combine 2 "Champion Mastery Tokens" with a Champion Shard or Blue Essence (which really means blue essence because getting the champion shard you want out of a chest is unrealistic).

I did get an S rank game on Fiora this morning, but I can't seem to find any "Mastery Tokens" anywhere in my hextech screen or player stats page. Am I supposed to see one somewhere? Or do I not get anything until I get the second S rank game? I would imagine anything I need would appear in the hextech tab because I need blue essence.

If I'm missing something please let me know, because I'm pretty lost here and just going to go for another S rank game to see if anything changes.