Hello Everybody
Here is the table of contents(TOC) for a step by step lessons on folded envelopes. 
All sub topics are videos showing the sequence of folds to fold envelopes. 
Videos of some topics has been provided under respective topic.
Step by Step approach to learning origami envelopes
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Lesson 1
    This lesson shows traditional envelope folding sequence with different measurements.
    Basic 1 (2 models with square) 
https://www.youtube.com/watch?v=vdscbiSHrXc
    Basic 2 (2 models with square)
https://www.youtube.com/watch?v=mYWVJxh9tt8
    Basic 3 (3 models with square)
    Basic 4 (1 model with square)
    Basic 5 (3 models with A4)
https://www.youtube.com/watch?v=HZ9e5mugHcM
    Basic 6 (1 model showing two side folding methods)
https://www.youtube.com/watch?v=W0diQt7g9pU
    Basic 7 (Variation: 4 models with square and A4)
Lesson 2
    This lesson shows envelopes with exploring as main focus.
    Exploring with Kite fold envelopes (3 models)
    Exploring with five sided envelopes ( 5 models)
    Exploring with six sided envelopes (7 models)
    Exploring with 5 rows envelopes ( 8 models)
    Exploring with Button lock envelopes(5 models)
Lesson 3
    This lesson shows a few varied envelopes    
    More models( 6 models)
Lesson 4
    This lesson shows envelopes with irregular sides.
    Odd shaped envelopes(3 models)
Lesson 5
    Customised envelope(1 model)
Conclusion
Greetings
Swamy
			
			
									
									
						Step by Step Lesson on origami envelopes(version 1)
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