My little seedlings are getting a big squished in their cell packs. I don't listen to my own advice when it comes to planting only one seed in each. It is time to transplant when the seedlings get long & leggy or when they get their first true leaves (they ones that actually look like tomato leaves - also start to smell like tomatoes)
Here's me starting to prep. Get a large container to mix soil in. I use a lot so I use a big rubbermaid. First I put 1/2 pro-mix (peat & vermiculite)
Then add 1/4 top soil
And 1/4 compost (if you have more, you can use more compost - I also water mine with compost tea so don't use as much to start)
Add water. Enough to get all the soil moist, but not soaking!
Then the fun dirty part! Mix all the soils & water together
Then get some clean pots. I re-use mine, so I washed them in bleach & soap first. You can use many things, but make sure they have drainage.
Fill the pots 3/4 with mixed soil. You need to leave room to bury the seedling. Leave more room if the plants are already bigger than mine pictured
Bury the stem plant into the soil, leaving green above the soil.
Then make sure you label the plant!! Water regularly. They will even appreciate a fan on them to help make them stronger and prevent mould.