Vowel placement logic - why is the 'i' sometimes before the consonant?

I'm a total beginner and the Lao script is absolutely throwing me off. I get the consonant-vowel-consonant structure, but I keep stumbling over vowel placement—like how some vowels appear to the left or top of the consonant rather than following it linearly. Is there a mnemonic or a specific way to visualize the 'cluster' of a Lao syllable to stop me from reading the vowels in the wrong order?