[wulf]

Like Andrew, I can only see the third shot. Two suggestions based just on that:

1. Unless the spider is sitting very still, it is probably easier to practise on inanimate subjects. Remove variables like the subject moving (or being blown about the in breeze) so you can set up the shot at your leisure (and experiment with different settings for the same shot).

2. The big challenge when focusing small things is the minimal depth of field. You've chosen an angle where the spider has a lot of depth; above or below is flatter and thus easy to catch all in focus.

Wulf

ps. Are you using a tripod for these shots or handholding? If hand-holding, you probably need a faster shutter speed and thus more light from ISO / aperture or external sources.