Starting from scratch would be tough until you get the hang of all the different options involved, but for now, you can just right-click on an effect that is similar to what you want to accomplish, and choose "duplicate". Then, open up your newly duplicated effect and give it a new ID and Name of your choosing. Then you can just edit whatever things you want to change, and it will remain mostly the same as the original effect besides the changes you've made. When you close the window, it will ask you if you want to make a new form, just click "No" (assuming you've already duplicated the effect--choosing yes will produce an additional duplicate, which you dont want) and then confirm with a "Yes" to the second popup.
So if you wanted to make healing hands an aimed spell, you could duplicate it and just changed the delivery type to aimed. It should work essentially the same, except that rather than instantly healing whoever is in the crosshairs, it will instead be (invisibly) shooting a "projectile"/stream at the target, kind of like the flames spell. This would be most noticeable if you were turning/moving while casting it, where it might take the spell a second or two to "catch up" to the cursor, unlike the original healing hands spell.
Reading the CK wiki should give you an idea what some of the other options will change in your new magic effect.