A real easy way to get your seeds off to a good start is to do this:
Use supermarket pots, the ones the fresh flowers are sold in, in morrisons they sell them for £1 for 8.
Use your favourite compost, I add vermiculite for drainage, fill pot to three quarters full, and water, sow seeds as packet says, cover with compost as required, and pat down gently.
Use a plastic bell cloche, diameter about 30cms, over the pot, this will fit snugly as its slightly too big for the pot, so you just wedge it firmly on.
Place in a sunny part of the garden or patio.
Open vent on top of bell cloche on hot days or as required.
Thin out if needed after germination.
When it comes to planting in final position just a small hand trowel or even a dinner fork will do. Just be quick, as the roots don't have a lot of soil around them.
This works well for making small plugs for the allotment, and also garden annuals. The big outlay is for the cloches, but they will last for years if you wipe and store safely after use.