Add pipx install instructions + explanation

Author: sjvrijn

README.md

@@ -48,17 +48,26 @@ There are multiple scenarios to use this template:
 [Scenario 2](#scenario-2-apply-to-pre-existing-code): Applying the template to some pre-existing code
 [Scenario 3](#scenario-3-updating-a-template-made-package): Updating a package made with the template
 
-In all three scenarios, you will need to install copier first:
+In all three scenarios, you will need to install Copier first, which we
+recommend doing with [`pipx`](https://github.com/pypa/pipx):
 ```shell
+python3 -m pip install --user pipx
+python3 -m pipx ensurepath
 pipx install copier
 ```
 
+> [!NOTE]
+> Note that it is also possible to install Copier with regular `pip`, but that
+> Copier will then be installed in your common environment and may cause
+> conflicts with its dependencies, while `pipx` will install Copier in a
+> separate and dedicated environment.
+
 ### Scenario 1: Create a new package
 
 
 #### Step 1/2: Create the files and directory structure
 
-Run `copier` with the template:
+Run `copier copy` with the template:
 
 ```shell
 # Notes:
@@ -155,7 +164,7 @@ containing your existing code rather than a new one:
 copier copy https://github.com/nlesc/python-template.git path/to/existing/code
 ```
 
-This works because if `path/to/destination` already exists, `copier` will
+This works because if `path/to/destination` already exists, Copier will
 update what is already there by either adding new files or updating
 existing files. Copier will ask to overwrite any files that resulted in
 conflicts. Especially if your files are already under version control, it is
@@ -171,14 +180,18 @@ created project using the `copier update` command. This has two effects:
 2. You can change any of your previous answers to apply these changes
    throughout your entire project.
 
+> [!CAUTION]
+> Do not manually update answers in `.copier-answers.yml`,
+> as it will result in unexpected behavior.
+
 ```shell
 cd path/to/project
 copier update
 ```
 
 If you don't want to change any of your answers, but only want to update your
 project according to the latest template updates, you can provide the
-`--skip-answered` option. This tells copier to reuse all of your previous
+`--skip-answered` option. This tells Copier to reuse all of your previous
 answers, and simply bring in all updates from the template into
 your current project, such as updating which Python versions are supported.
 You will still be asked to answer any new questions that have been added to