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textcomp’s texttildelow is actually quite a bad choice: it’s too low for most fonts.

A much better rendering can be achieved by the following, which tweaks the appearance of the (otherwise too wide) $sim$:

{raise.17exhbox{$scriptstylesim$}}

This was taken from the Arbitrary LateX reference … the page also provides a good comparison sheet:

When used in texttt, I would add a mathtt around the tilde, to make it fit the font better:

{raise.17exhbox{$scriptstylemathtt{sim}$}}

The difference is small but noticeable.

You can also use the "plain TeX" method of indexing the actual ascii character in the current font:

char`\

char`~

I often use the former for writing macros that need the backslash in the typewriter font; textbackslash will sometimes still use the roman font depending on the font setup. Of course, if you're using these a lot you should define your own macro for them:

newcommandSLASH{char`\}

I occurs to me that you might be trying to type URLs. In that case, the url package takes care of everything for you:

usepackage{url}

...

url{somewherehome~will}

For paths (i.e., local files), there is path, working the same way as url, just providing the correct links in case hyperref is loaded.

If you are loading hyperref there is no reason to load url as well.

Well if that isn't annoying:

 textbackslash

 texttt{char`~} or $sim$

Thank for reading. :)

Edit: added code for tilde.

Hmm; textbackslash (mentioned by others) isn't in my reference book (Kopka and Daly).

At any rate, math mode provides sim, backslash, and setminus (the latter two appear to look the same and differ only by spacing in math mode).

My LaTeX book – which, as you would expect, features the extensively – seems to use the verbatim environment. For example, this code:

begin{verbatim}

 addtocounter{footnote}{-1}footnotetext{Small insects}

 stepcounter{footnote}footnoteext{Large mammals}

end{verbatim}

Produces this text in the book:

 addtocounter{footnote}{-1}footnotetext{Small insects}

 stepcounter{footnote}footnoteext{Large mammals}

The verb command is similar, but the argument must be on one line only. The first character after the b is the delimiter; for example:

verb=emph{stuff}=

will produce

emph{stuff}

So you could presumably get your backslash by typing:

verb==

You can also add a * – i.e. verb* or begin{verbatim*} – to make whitespace visible.

It is interesting to speculate how you would get an example of a verbatim environment into a document..
(using verb to do the last line, I guess)

For the tilde, you can use empty curly brace pair. That puts the "over the letter" tilde over an "empty" letter, so it's placed upward.

My tilde~{}here

From https://faculty.math.illinois.edu/~hildebr/tex/bibliographies.html

"... tilde symbol (~), which without
special coding gets interpreted as a
blank space, and therefore needs to be
escaped by a backslash (~) or
replaced by the math "twiddle" symbol
$sim$. Fortunately, there is a
package, url, that provides a
painless way to typeset URL's. To use
this package available, add

usepackage{url}

near the beginning of the document,
and enclose any web and email
addresses in the document in
url{...}:

url{http://www.math.drofnats.edu/~gauss}

url{gauss@math.drofnats.edu}

..."

I hope this could help you in typewriting a regular tilde character.

Personally, I learned more actually changing the catcodes myself :)

begingroup

  catcode `~=11

  gdefmytilde{~}

  catcode `|=0

  catcode `\=11

  |gdef|mybs{}

|endgroup

and then something like

This is a tilde: mytilde

This is a backslash: mybs