It is annoying to hear "Next Slide Please" frequently, when you are attending a webinar through a service such as WebEx. These tips may help you avoid falling into the "Next Please" pit.
1. Try to operate the presentation yourself. If someone else such as a moderator had initiated the presentation, he can pass the operator rights to the presenter, in many systems such as WebEx. Use this effectively.
2. If for some reason, you are not comfortable with operating the slides yourself in the system, keep the moderator next to you, so that you can signal verbally instead of announcing "next please" to all the attendees.
3. If #1 and #2 could not be achieved due to the technical and other difficulties where the moderator has to be remote, practice and sync, so the operator/moderator knows when to go to the next slide just by listening to you talk.
4. If time pressure prevents you from #3, try to avoid putting too much bullet points in animation mode inside the slides. This will at least avoid or mitigate the requirement to say "Next please" inside a single slide.
Overall, just avoid the need for next please.