For new stitchers Id recommend the exact opposite that Nekostitch did. I would suggest starting with a design in only one or two colours, maybe a silhouette. Make it any colour you wish, but focus on the stitching and even spacing, rather than changing lots of colours.
Best tip I saw from someone for scissors was instead of going to the craft department, go to the beauty department and look for cuticle scissors. They are small, very pointy and have a curved tip, so you can get close to the fabric and cut just the threads that you want to. And they are cheap - I got mine for $3.