Drawing tools for architects
During old times when term architecture in software or IT was not popular hardly people were using UML diagrams to represent their design. Slowly this became a documentation practice of weeks and months, even some teams were developing software and then for compliance creating design (UML diagrams), I guess the good use of that was for maintenance. One who maintains the software would refer to that design.
I had been of opinion that design or architecture is for taking technical decisions to achieve business requirements and if these decisions can't help building the system and can't help in achieving functional and non functional requirements, better is call it documentation. Too much upfront design and once for all is also not practical, but you will have to understand the requirements, analyze them, take design decisions, build an increment and review the design decisions if quick demonstration of the software to the customer brings new requirements or new discoveries about old requirements. In this case you may have to update your design decisions. Design (thinking to take technical decisions) is still required but it should be a collective approach with the team, doing it on board, brainstorming with those who are going to implement it. Take a picture from the board and attach it in the document or project wiki wherever you want to keep it for reference. Models are a way to present your design ideas. Design (and architecture) is craftsmanship.
Sometimes now too you have to deliver something fast, you already have lots of experience so sometimes you define it upfront and try to implement it quickly (and forget the collective approach mentioned above). This may be the only option in some cases but should not be default way of doing it.
There are some interesting tools (some free and some commercial) which can be used to represent your design ideas and system:
Diagrams using AWS and other cloud provider icons
Service/Product: diagrams.net (earlier known as draw.io)
Company: "The draw.io plugins are owned by https://seibert-media.com/, a Germany consultancy that specializes in Atlassian and Google Cloud. The plugins are developed by the team who build the diagrams.net open source editor that is used in draw.io".
Type: Online (and download of the product diagrams.net is also available)
License: Commercial opensource. Free
Description: There are lots of shapes covering various cloud platforms, UML, Archimate, C4 model and much more.
Service/Product: VP Online Diagrams
Company: Visual Paradigm
License: Commercial ( VP Online Express Edition is a free online drawing software for personal and non-commercial use only. Watermark will appear on images exported under Express Edition.
Description: There are lots of templates to start with or you can create it from scratch. Use AWS icons to represent your design ideas.
Note: There is a downloadable software from visual paradigm which is not what we are talking about here.
Service/Product: Lucid chart
Company: Lucid Software Inc
License: Commercial. There is a default free account with limited features but no detail available.
Description: There are lots of templates but most of them are premium so no access for free. Few are free templates. You can start with blank template and use shapes for AWS, Azure and many others.
License: Free online version with limited features available.
License: Commercial. 14 days trial.
EA (archimate) tools
Company: archi comunity
Design tools (UML Modeling)
Service/Product: diagrams.net (earlier known as draw.io) also has support for UML notations
Service/Product: websequence diagrams
License: Commercial (Free version with limited features
Description: Create sequence diagrams by writing text without mouse. it is an interesting tool with cool feature text to sequence diagram
Modelio (Free), Umbrelo (Free), BOUML (Free again now), UMLLet(Free), umletino.com (web version), DIA (very old release available, free, various types of diagrams),
MagicDraw (commercial), Enterprise Architect from Sparx System(Commercial), IBM Rational Rose (Commercial) . StarUML (commercial)
Cacoo (commercial), Lucidchart(Commercial), Creately (commercial), Coggle (commercial), yED(Commercial), SmartDraw (Commercial), EDrawMax (Commercial), Terrastruct (Commercial)
Service/Product: Plant UML
Type: Online server as well as downloadable software