Question about how to write extended kana

In the extended, combined kana characters such as gyu, kyu, kya, etc, is the smaller kana symbol written after the larger kana symbol? And are there any variations in the writing rules between hiragana and katakana for those characters? It makes sense that it would be, but I'm just confirming so that I don't develop a poor writing habit, and I've looked a lot of places for this information but couldn't find it. Any info is appreciated.

Yes, small symbol after larger symbol.

Imagine 2 boxes of the same size, and divide the second box into four smaller boxes with dotted lines.

Larger symbol occupies the whole big box, small symbol occupies the bottom left small box.

If writing vertically, larger symbol occupies the whole big box, small symbol occupies the top right small box.

Same rule for Hiragana and Katakana.

Just to add, I hope you are aware that it's 2 different symbols (2 letters).

For example, ぎゅ is the letter ぎ and another letter ゅ We call the latter a "small ゆ"

Perhaps you are a bit confused since ぎ is one letter (and not き and another " thing).

Letters like が and ぱ are considered as one letter respectively, while things like きゃ or たっ or わー are considered as two letters respectively.

Hope it helps.

http://u-biq.org/hiragana/kya.html

http://www.kodomo-kotoba.info/booklet/pdf/ws_hiraganar-renshucho_50onj...
pages 30-31

Thank you all for your posts. My question has been answered.