How to establish a cohesive & consistent Instagram theme is a topic I get asked about quite a bit. I'm spilling my secrets with all my tips on how to curate your instagram and maintain the theme.
1/ Use a feed planning app
It can be difficult to achieve a consistent theme without planning out your feed first. I use the app UNUM to rearrange my photos in a grid before posting. Another app you can use is Planoly.
2/ Use the same filter on all your posts
Edit all your posts with the same filter to keep them cohesive. Apps like VSCO and Lightroom have options to copy and paste the same filter onto new photos so you don't need to start from scratch each time.
3/ use colour as a motif
Featuring the same colour throughout the majority of your photos can also draw all your posts together. The stricter you are with this, the more cohesive your feed will look. Spread out photos that don't fit this colour scheme.
4/ Match your whites
Take a look at the white tones in your photos and compare them in your planning stage. You can create a consistent theme by making sure all the white tones match each other.
5/ Use Negative Space
Negative space is the space that surrounds your main subject. Increase this space in your photos or alternate negative space images with close ones in your planning app. This gives your feed a fresh, less cluttered look.