You can use a virus a means of introducing the foreign DNA into the host genome. Also called tranduction, it is efficient but can lead to unwanted effects sush as activation of oncogenes or the interruption of genes due to random insertion of DNA in the genome. Aside from this, one can also use chemicals such as calcium phosphate which is positive and can complex with the negatively charged DNA. Electroporation can also be a viable method since it makes the cells more succeptible to nucleic acid transfer. For more information, please refer to the source below. Good wishes