You're such a hot pot head.

No, that's not potting on. Potting on is where you remove it from one size pot and on to a larger one.

What you are planning to do is known as "pricking out" - the act of taking seedlings from their original tray or pot and transfering them to their first individual pots.

Top tips - hold them by a leaf, not by a stem. If you clasp them by the stem, you'll bruise the stem and they'll collapse and die.
You'll need a good "dibber" (you couldn't make these terms up, really). Whilst you can purchase fancy stainless steel ones, a Bic biro will do just as well. Use it to help ease the plant from the compost without breaking the roots, and also to make a little hole in the new compost to insert it in.
Be sure to water your new plants in - not just because they need water, but also because watering them helps to settle the soil around the roots.
Don't over-firm the compost - just gently press it down with your fingers before watering it in. You want to retain some "air-filled porosity" in your compost - in other words, it needs to be slightly open, not compacted.

I find that when pricking out with your dibber, going commando adds certain pleasing thrills to the act of gardening.

Karen: I'd put them individually in pots that are about 3 inches in diameter. When they are established in this size, then you can put them into something bigger - and perhaps then pack (say) three plants into one big tub. Looks like you have quite a few plants there, so putting them into individual pots gives the opportunity to pass them to friends once they are established, if you have too many. (Too many plants, that is, not friends).
Robert Dyas or Woolworths (larger branches) are good places for pots. Morrisons had some recently too.

Pete: blue.

Adhoc: people going commando for pricking out may find that their dibber is handier than they thought.

Oh, and be prepared for some "pricking out losses" - <rolf>a few of the little fellas aren't going to make it</rolf>.