Just gonna agree with meal planning and freezing food. Having casseroles in the freezer is SO helpful when I'm feeling lazy/busy.
My added tip - I LOVE using dissolvable labels (like this: http://www.amazon.com/Ball-Dissolvable-Labels-Jarden-Brands/dp/B004NGVIIK). I find dry erase markers can rub off or leave marks over time, but these you can write on with a normal pen or sharpie and stick it on almost any kind of container. (Then they wash off and don't leave a sticky residue!) The next step is just getting in the habit of labeling! :)
If it’s worth it to you Ball makes dissolvable labels. They come if in the dishwasher or with a brief soak in the sing with no residue at all.
Ball makes dissolvable labels that stick really well but disintegrate when you wash the container.
Ball Dissolvable Labels, Set of 60 https://www.amazon.com/dp/B004NGVIIK/ref=cm_sw_r_cp_api_glt_fabc_YAZ4GSC3DZWJB0Z7BFS7
Dissolvable jar labels These are great and wash off with water
I use Ball Dissolvable Labels. You can pick them up just about anywhere.