The reason that New York Giants receiver Odell Beckham Jr. is able to complete ridiculous catches (while making them look routine) is because he practices snagging footballs in just about every way imaginable.
Both Beckham and Miami Dolphins wideout Jarvis Landry, his former teammate at LSU, posted videos of their workout with a JUGS machine.
Update from Wednesday, July 8
Beckham showed just how crazy he can get with catches in the latest video:
--End of Update--
Warning: Videos contain NSFW language.
Whether it involves standing up, laying down or just using one hand, there may not be a pass Beckham can't catch.
It may seem unnecessary to practice some of these catches, but it's better for a receiver to be prepared in the unlikely event he needs to make an unusual grab.