If you do not have permission to install apps in your company’s Slack workspace, there are a couple of options for getting someone (i.e., a Slack administrator) to do it for you.
The first is just to identify who – at your company – can install Slack apps and ask him or her to add the Please Share app. When reaching out via email or through Slack, you should share a link to the Please Share website or Slack app directory page – both of which include Add to Slack buttons.
Alternatively, your company may have a process – where you can submit requests (see Send and app request) to install apps – directly from Slack.
In either case, when the Please Share app has been added to Slack, you should request that your company’s Slack admin add you as the Please Share admin – when prompted to do so – once the app has been added to your Slack workspace.