自
=
丶
+
目
:
Mnemonic symbol: a hand mirror, which someone uses to look at themselves.
The Eye of Providence (目) is looking at itself (自) in a handheld mirror (自) in the space station's bathroom (Ø4). It think it's indeed looking very good, since Zorro (z) attached a petal (丶) to its eye (目).
由
=
丨
+
曰
:
Mnemonic symbol: 自由古巴, a cuba libre. The character 由 itself even looks like a cuba libre.
Maud Younger (y) is taking part in a charity auction in the outhouse's kitchen (ou2). She is auctioning the dinosaur bone (丨) next to her and is speaking into a microphone (曰). In the other hand she is holding a cuba libre (由), and she is already quite drunk.
在
=
一
+
亻
+
土
:
Zorro (z) and Rosa Luxemburg (亻) exist (在) in the airplane's bathroom (ai4). Rosa is in the middle of balancing a flute (一) on her head and on a pile of clay (土). Zorro uses his rapier to inscribe "Z" into the flute, so as to mark that the pronunciation of "在" begins with "z".