All you have to do is buy Len cosplay and wear it whenever you can! If wig is not comfortable for you or you fast sweat you can bleach your hair and do small ponytail. To be more Len and dress not always only one costume you can buy more cosplays from diffrent modules!
Easily accessible costumes:

Muse Dash[pl.aliexpress.com]
Punkish[dokidokicos.com]
sour[www.amazon.pl]

Become bananas eater no.1! Eat bananas, drink banana juice etc!

Because most of 𝓯𝓻𝓮𝓪𝓴𝔂 vocaloid songs are featuring Len you have to be a little bit 𝓯𝓻𝓮𝓪𝓴𝔂 but thats okay because u are Len!

You have to buy a lot of yellow things like decorations to your room etc because yellow is Len color!

Thats all! Thanks for reading my tutorial, I hope you enjoyed it!