You can put some pesticide powders outside your hours which will kill spiders who come in contact with it. For the inside of your home you can purchase an odourless spray. In order to get rid of the cobwebs there are special cobweb eliminators you can use — just put some on the webs and they will be gone in no time. You should also vacuum the spaces where spiders are most active, and vacuuming frequently (including walls and ceilings) can be a long term solution but it is not always realistic and you may need to call professionals. You can also try to eliminate the sources of bright natural and artificial light which attracts spiders and provides a food source for them.
The trick with these natural DIY solutions is that they may work in some cases and in others they won’t so you have to make sure that you are not putting in too much time and money into something that may fail completely. You should always count on experts to eliminate the problem painlessly and quickly.