Slackware installs TeX Live by default. However, extra packages and documentation require root permissions to install. This HOWTO explains how to install TeX Live as a non-root user.

# download the installer
cd /tmp
wget https://mirror.ctan.org/systems/texlive/tlnet/install-tl-unx.tar.gz
 
# uncompress it
tar xvf install-tl-unx.tar.gz
 
# install it
(
cd install-tl-[0-9]*
version=$(sed '/version [0-9]/!d; s/.*version //' release-texlive.txt)
./install-tl \
	--no-interaction \
	--texdir=$HOME/usr/local/opt/texlive/$version \
	--texmflocal=$HOME/usr/local/opt/texlive/texmf-local \
	--texmfhome=$HOME/usr/local/share/texmf \
	--scheme=basic \
	--paper=letter
 
# create a symlink for paths
cd ~/usr/local/opt/texlive
ln -s $version current
)
 
# delete the installer
rm -rf install-tl-*
 
# add paths to TeX Live
cat << 'EOT' >> ~/.bash_profile
 
# TeX Live
export PATH="$HOME/usr/local/opt/texlive/current/bin/x86_64-linux:$PATH"
export MANPATH="$HOME/usr/local/opt/texlive/current/texmf-dist/doc/man:$MANPATH"
export INFOPATH="$HOME/usr/local/opt/texlive/current/texmf-dist/doc/info:$INFOPATH"
EOT
 
# read them into the current session
. ~/.bash_profile

Use tlmgr (already installed with TeX Live) to install new packages.

You can use Kile (already installed by Slackware) to edit and compile LaTeX files. If you like Vim or Neovim, VimTeX is a great plugin.

For reference management, JabRef is good for BibTeX. I can install it for you.