I couldn't see your photos. Do try to post them in the optional link URL so we can all see what you have.

Anyway, it's all very easy. Use triple mixes to top off any garden bed. When you do clean beds, remove all weeds. Triple mixes are not too rich for plants. You can get them premixed in bags already. I also like using Loblaws' black earth and a bag of composted manure like cow or sheep manure. There is no smell so don't worry. It's been aged for a couple of years and so any weed seeds in there are been killed off. I also add bone meal.

You can certainly add annuals to your garden bed. Before transplanting, water your plants well first. Then when you transplant, do it early in teh day or late afternoon. Never during a time when the sun is particularly hot. Also never fertilize the same day of of transplanting. Fertilizers can burn off plants. I would apply it only in the 2nd week or so.

Having said this, I prefer to use perennials for my bed because they come back year after year and there's very little maintenance. I water maybe once a week and my plants would be fine.

If you have any more questions, feel free to ask.

Hey stegen123,
My only tip to you would be the magic word MULCH!
Once you've added the topsoil (if you really need to do so, mind you) and/or a bit of compost around the base of each plant, mixed in with the soil, my recommendation would be to add a biodegradable mulch (not that way-too-much overused cedar mulch) called RWC or ramial wood chips(in Qu�bec it's called BRF or "bois rameal fragmente"). This stuff is great! It looks like small cut-up branches. Excellent ground cover, lets water in and keeps most weeds out AND it slowly degrades over time to enrich the soil and plants.
I'd also suggest that you get to know the plants in your beds. Conversation is optional, heh heh
Happy gardening, you won't regret it but be warned: It's addictive... but the healthy kind lol