1
Look at that huge spider!
Sign 'spider' and pair it with wide eyes and a surprised or disgusted facial expression to emphasize the size of the spider and your shock at seeing it.
2
I am scared of spiders.
Sign 'me', then 'scared', and finally 'spider'. Make sure your facial expression matches the feeling of fear, perhaps by pulling your head back slightly as you sign.
3
The spider is crawling up the wall.
Start by signing 'spider' in the normal way, but instead of moving your hands forward, move your crossed hands upward to visually demonstrate the spider's actual path up the wall.