Hi Sue, I too have a hard time cutting the fabric. It scares me and it hurts my back to do it. As for room to use a design board, I got 2 yards of white flannel and I tack it up in front of my closet. I use it to lay out the design and then I take it down again. I have a wide closet so I tack it to the moulding over the top of the closet doors. That way you can't see the tack marks. I use straight pins to tack it. You can hardly see the spot where you tack it up and when I am done I take it down, roll it up and put it away. It works great for me. I did zigzag stitch the edge of the flannel so it stays together very well. I also made sure to get the 90 inch wide flannel. It is plenty big enough to use for designing and it doesn't get in the way of the family that way.
I sew with a Singer Quilting machine. So far it has been a good machine for the small price I paid.
Someday I would love a Bernina or a phaff. I really loved the Phaff but whew they are expensive!
The nerves will calm the more you sew. You will do great. The main thing is to have fun and be creative. I had a good friend that used to say "create something new everyday." She was amazing and we all miss her greatly. We lost her in 2006 I think. It's been too long anyway.
Just have fun and the nerves will disappear. Hugs, Jan