How to plan a database application

My excercise is growing so complicated that I loose oversight. Question is there a software to plan a complete database application (tables, relationship, fields, forms, menus)? Just downloaded yED for Linux but have yet to install and evaluate. Or how would you do it?

The objective is to develop a database application for orthopaedic workshops from the view of the user. This is in order to work effectively as many of us are not computer-experts, even lacking fast internet access.

The result will not be for real use but to show a programmer what a user might want to. E.g. a programmer will no know that in order to create a estimate of cost we will have to use a measuring chart. To demonstrate workflow and data required is the objective, it is then much easier to code it.

If it has commercial potential it might be developed in a different database than base but this is a professionals decision in the future.

Output → Input → Data Structures → Processes → Review
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Try the Getting Started or Base Guide for direction.
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The main thing with databases is normalised tables. Agile software development (ie prototype / suck it and see / Pareto principle) has a lot of support.

Playing around it looks that I have to create two different schemes. On for the back-end showing tables, fields and relations like in the tool “Relationsships” in Base. The other for the front-end or user-interface listing forms, data and actions like opening what other form when . . …