I wouldn't worry too much about the yellow streaks on the leaves, I imagine it would be a very rare daylily garden that doesn't have some of that on the older leaves. If you started getting a lot of leaves like that then it might suggest a problem. The last picture, though, looks somewhat like leaf scorch, see:
http://hyg.ipm.illinois.edu/pa...
Early morning is the best time to water. You can water in the evening instead if there's no risk of fungal diseases. The amount to water, and the frequency, depends on the weather and the soil type. The best way to tell if you need to water is to dig down near the plants with a trowel and check to see if the soil looks damp. If it does you don't really need to water. If you can water less frequently but give more water each time it is better for the plants as it is less likely to encourage shallow rooting. With clay, though, you may have problems with pooling on the surface if you do that and the infiltration rate is slow An organic mulch would help keep the moisture in and will gradually improve the soil (make sure the soil is watered or rained on before applying the mulch). The concrete structure beside the plants in the picture will also be exaggerating the hot dry weather.
Re earwigs, I use Safers insecticidal soap, organic and made especially for plants, as it is less likely to burn the leaves than the home-made solutions with dish soap. You may not be able to get that there though. I just carry a hand-sprayer and zap the earwigs individually as I see them. The small amount of soap that hits the leaves that way is less likely to do damage. You'll get more of the earwigs if you go out at night.
Just to clarify something, a lot of articles on home-made insecticides call them "natural", I'm not sure why because regular dishwashing liquid certainly isn't natural and nor are some of the other ingredients often included.
