If you are running an online store, there are some aspects to consider aside from the general SEO advice. Making your product pages as complete as possible and leaving no questions open is paramount. That way, you can avoid that potential customers leave your website without buying anything, for instance in cases where necessary information was missing.
Try to look at your store from a customer's perspective and imagine what information you'd be looking for in your store.
Which product information is especially important?
If you provide extensive product information, meaningful product images or product videos for instance, this will convince your visitors to stay on your website for a longer duration, which in turn can have a positive effect on ranking. High quality product text is a good opportunity to use keywords on the respective product page which will make it easier for your products to be found on Google.
Why should texts not be copied from other places?
In case you're selling products from another manufacturer in your online store, then you should make sure not to copy the manufacturer's texts word for word. Instead, describe the product in your own words and ensure that your customers get to read an individual product description.
Copying the product description from the manufacturer, i.e. from their website or if you're using the official description that many other store owners use might lead to Google marking your content as duplicate content because Google already knows it. That could negatively affect the ranking of your website or online store. Uniqueness is key here as well.
What to do if a product is temporarily unavailable?
Instead of removing a product once it is temporarily unavailable, leave it in the store and label it accordingly. This happens automatically in your Jimdo store once the stock reaches zero or you set the product to not available.
In addition to that, you could add a text field to the product page, stating when the product is expected to be in stock again. Doing so, the page does not need to be re-indexed by Google and reestablish its ranking.