If at all possible, I always recommend taking a beginner's class at a local quilt shop, school or church. This will teach you proper ways for cutting, pressing and sewing a 1/4" seam. All are important for a successful project. The added benefit is that you will have an instructor to ask if you get stuck. I had an extensive sewing background and am glad that I took the class. I don't want to discourage you, but the 2 patterns you refer to in your post may present a challenge. The triangles will all have bias edges and may pull out of shape with handling. Also, her instruction to let the tips overhang and 'equal amount' is good, but I made a similar pattern and had a difficult time keeping them aligned. The other pattern has curved piecing, and the curve is quite tight, which may cause difficulties. You may want to look at a pattern based on squares for a first go. If you do want to go forward with one of your example quilts, I would go with the triangles. Starch the fabric well to avoid stretching the bias, and only cut a few pieces then sew to see how it goes before cutting all your fabric.